Medical treatment endoscope

ABSTRACT

The medical treatment endoscope according to the present invention includes a sheath having a flexibility; at least one arm member having a bending part that projects out from a front end of the sheath and performs bending actions; an open/close mechanism which directs the arm member from a direction along a central axis of the sheath to a direction deviated from the central axis of the sheath, and from a direction deviated from the central axis of the sheath to a direction along the central axis of the sheath; and a viewing device and an illuminating member that are disposed to the front end side of the sheath.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application is a Divisional Application based on U.S. patentapplication Ser. No. 11/809,488, titled “MEDICAL TREATMENT ENDOSCOPE”,filed Jun. 1, 2007, which is a Continuation In-part Application (CIP)based on U.S. patent application Ser. No. 11/652,880, titled “MEDICALTREATMENT ENDOSCOPE”, filed Jan. 12, 2007, which is a CIP based on U.S.patent application Ser. No. 11/435,183, titled “MEDICAL TREATMENTENDOSCOPE”, filed May 16, 2006, which is a CIP based on U.S. patentapplication Ser. No. 11/331,963, titled “MEDICAL TREATMENT ENDOSCOPE”,filed Jan. 13, 2006.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an endoscope apparatus.

2. Background Art

Laparoscopic surgery is a conventionally known technique that has beenemployed when performing a medical procedure such as observation ortreatment of the internal organs of the human body. Rather than making alarge abdominal incision, laparoscopic surgery provides for theprocedure to be carried out by making several openings in the abdominalwall, and inserting a laparoscope and surgical instruments such asforceps into these respective openings. This type of surgery offers thebenefit of being less invasive on the patient, since only small openingsare made in the abdominal wall.

As a method of even further reducing stress on the patient, it has beenproposed in recent years to carry out medical procedures by inserting aflexible endoscope into the patient via a natural opening such as themouth, nostrils or anus. An example of a medical treatment endoscopeused in such procedures is disclosed in U.S. Patent ApplicationPublication No. 2005/0065397.

In the medical treatment endoscope disclosed in this reference, armmembers that have a bendable end are respectively inserted into aplurality of lumens disposed within a flexible inserted part that isinserted into the body via the mouth of the patient. By insertingrespective instruments through these arm members, the procedure site ofinterest can be approached from different directions with the variousinstruments. Accordingly, a plurality of procedures can be carried outin continuum by means of a single endoscope inserted into the body.

SUMMARY OF THE INVENTION

The medical treatment endoscope according to a first aspect of thepresent invention includes a sheath having flexibility; at least one armmember having a bending part that projects out from a front end of thesheath and performs bending actions; an open/close mechanism whichdirects the arm member from a direction along a central axis of thesheath to a direction that deviates from the central axis of the sheath,and from a direction that deviates from the central axis of the sheathto a direction along the central axis of the sheath; and a viewingdevice and an illuminating member that are disposed at the front endside of the sheath.

The medical treatment endoscope according to a second aspect of thepresent invention includes a sheath having flexibility, in which a firstlumen with an open end is formed; at least one arm member having asecond lumen with an open-end extending in the axial direction intowhich a procedure device for performing a procedure in an organ isinsertable, and a bending part for performing bending actions, a frontend of the arm member projecting out from the open end of the firstlumen; an open/close mechanism which directs the arm member projectingout from the first lumen from a direction along the central axis of thesheath to a direction that deviates from the central axis of the sheath,and from a direction that deviates from the central axis of the sheathto a direction along the central axis of the sheath; and a viewingdevice and an illuminating member that are disposed at a front end sideof the sheath.

The medical treatment endoscope according a third aspect of the presentinvention includes a first sheath having flexibility and an open end; asecond sheath that is provided with a first arm member that has a frontend and a base end and is inserted so that the front end area projectsout from the first sheath, and that has a bending part that is freelybendable through manipulation by an operator; a third sheath providedwith a second arm member that has a front end and a base end and isinserted so that the front end region projects out from the firstsheath, and that has a bendable part that is freely bendable throughmanipulation by the operator; a viewing device that is independentlydisposed at the front end of the first sheath from the second sheath andthe third sheath, and is for viewing a target image; and an illuminatingmember that is independently disposed at the front end of the firstsheath from the viewing device, the second sheath and the third sheath,and is for radiating illuminating light on the target image.

The medical treatment endoscope according to a third aspect of thepresent invention includes a sheath having a flexibility; an arm meansthat projects out from the end of the sheath and is for performingbending actions; an open/close means which directs the arm means from adirection along a central axis of the sheath to a direction deviatedfrom the central axis of the sheath, and from a direction deviated fromthe central axis of the sheath to the direction of the central axis ofthe sheath; a viewing means for viewing an area further toward the frontend than the sheath; and an advance/retract means for advancing orretracting the arm means with respect to the sheath.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows the configuration of a tip end of the endoscope apparatusaccording to a first embodiment of the present invention.

FIG. 2A shows the configuration of a tip end of the endoscope apparatusaccording to the first embodiment of the present invention.

FIG. 2B is a partially enlarged diagram of FIG. 2A.

FIG. 3 is a cross-section viewed along line I-I of FIG. 1.

FIG. 4 is a view of the front end of the medical treatment endoscopeaccording to the first embodiment.

FIG. 5A is a perspective view showing the starting state of the armmember of the medical treatment endoscope according to the firstembodiment.

FIG. 5B is a view along direction A in FIG. 5A.

FIG. 6A is a perspective view of the front end showing the arm member ofthe medical treatment endoscope according to the first embodiment in theopen state.

FIG. 6B is a view along direction B in FIG. 6A.

FIG. 7A is a plan view showing the starting state of the arm member ofthe medical treatment endoscope according to the first embodiment.

FIG. 7B is a view along direction C in FIG. 7A.

FIG. 8A is a plan view showing the open/close mechanism when the armmember of the medical treatment endoscope according to the firstembodiment is in the open state.

FIG. 8B is a view along direction D in FIG. 8A.

FIG. 9 is a perspective view showing the operating part of the medicaltreatment endoscope according to the first embodiment.

FIG. 10 is a view along direction E in FIG. 9.

FIG. 11 is a view along direction E in FIG. 10.

FIG. 12 is a view along direction F in FIG. 11.

FIG. 13 is a view along direction G in FIG. 12.

FIG. 14 is a view showing the state in which one of the arm members ofthe medical treatment endoscope according to the first embodiment hasbeen moved forward with respect to the sheath.

FIG. 15 is a partial perspective view of FIG. 14.

FIG. 16 is a view showing the state in which one of the arm members ofthe medical treatment endoscope according to the first embodiment hasbeen moved forward with respect to the sheath, and further opened.

FIG. 17 is a partial perspective view of FIG. 16.

FIG. 18 is a view explaining the state in which the endoscope has beeninserted into an over-tube, and then inserted into the stomach, in anoperative procedure using the medical treatment endoscope according tothe first embodiment.

FIG. 19 is a view explaining the state in which the endoscope has beeninserted into an over-tube, and then inserted from the stomach into theabdominal cavity, in an operative procedure using the medical treatmentendoscope according to the first embodiment.

FIG. 20 is a view explaining the state in which the procedure is carriedout inside the abdominal cavity, in an operative procedure using themedical treatment endoscope according to the first embodiment.

FIG. 21 is a view of the front end of the medical treatment endoscopeaccording to the first embodiment.

FIG. 22 is a view showing the structure of the medical treatmentendoscope according to the third embodiment.

FIG. 23 is a plan view showing the structure of the front end of themedical treatment endoscope according to the third embodiment.

FIG. 24A is a view of the front end of the medical treatment endoscopeaccording to the third embodiment, along the H direction.

FIG. 24B is a side view of the medical treatment endoscope according tothe third embodiment.

FIG. 25 is an underside view showing the structure of the front end ofthe medical treatment endoscope according to the third embodiment.

FIG. 26 is a plan view of the front end of the medical treatmentendoscope showing the case where the arm member is closed.

FIG. 27 is a side view of the front end of the medical treatmentendoscope showing the case where the arm member is closed.

FIG. 28 is an underside view of the front end of the medical treatmentendoscope showing the case where the arm member is closed.

FIG. 29 is a view along direction J in FIG. 27.

FIG. 30 is a cross-sectional view along line II-II in FIG. 26.

FIG. 31 is a cross-sectional view along line III-III in FIG. 27.

FIG. 32 is a perspective view showing the operating part of the medicaltreatment endoscope according to the first embodiment.

FIG. 33 is a perspective view showing the operating part of the medicaltreatment endoscope according to the first embodiment.

FIG. 34 is a view along direction K in FIG. 32.

FIG. 35 is a view along direction L in FIG. 33.

FIG. 36 is a view along direction M in FIG. 33.

FIG. 37 is a schematic view showing the essential parts of the sheathadvance/retract mechanism.

FIG. 38 is a perspective view showing the open/close operating part.

FIG. 39 is a side view showing the open/close operating part.

FIG. 40 is a cross-sectional view along line IV-IV in FIG. 39.

FIG. 41 is a view showing the essential part of the vertical bendingoperating part.

FIG. 42 is a view showing the essential part of the horizontal bendingoperating part.

FIG. 43 is a view showing the structure of the tip of the medicaltreatment endoscope according to a fourth embodiment.

FIG. 44 shows an initial state of an arm member of the medical treatmentendoscope in perspective.

FIG. 45 shows an enlarged initial state of the arm member of the medicaltreatment endoscope in perspective.

FIG. 46 shows an open state of the arm member of the medical treatmentendoscope in perspective.

FIG. 47 shows an enlarged open state of the arm member of the medicaltreatment endoscope in perspective.

FIG. 48 shows an enlarged open state of the arm member of the medicaltreatment endoscope in perspective.

FIG. 49 shows an enlarged open state of the arm member of the medicaltreatment endoscope in perspective.

FIG. 50 shows a bending state of the arm member of the medical treatmentendoscope in perspective.

FIG. 51 shows a bending state of the arm member of the medical treatmentendoscope in perspective.

FIG. 52 is a front elevation describing a bending state of the armmember of the medical treatment endoscope in perspective diagram.

FIG. 53 shows an initial state of the arm member of the medicaltreatment endoscope in crosssectional view.

FIG. 54 shows a bending state of the arm member of the medical treatmentendoscope in crosssectional view.

FIG. 55 shows an initial state of the arm member of the medicaltreatment endoscope in crosssectional view.

FIG. 56 shows the arm member of the medical treatment endoscope incrosssectional view.

FIG. 57 is a cross-sectional view along the line I-I in FIG. 53.

FIG. 58 is a cross-sectional view along the line II-II in FIG. 53.

FIG. 59 is a cross-sectional view along the line III-III in FIG. 53.

FIG. 60 is a cross-sectional view along the line IV-IV in FIG. 53.

FIG. 61 is a perspective view of a tip of the medical treatmentendoscope.

FIG. 62 is a schematic representation of a modified example of themedical treatment endoscope.

FIG. 63 shows the medical treatment endoscope of FIG. 62 viewed alongthe line in front view.

FIG. 64 shows a bending state of the medical treatment endoscope of FIG.62.

FIG. 65 is a perspective diagram illustrating a bending state of the armmember of the medical treatment endoscope according to the firstembodiment.

FIG. 66 is a perspective diagram illustrating a bending state of the armmember of the medical treatment endoscope according to the fourthembodiment.

FIG. 67 is a view explaining the state where an overtube having themedical treatment endoscope according to the fourth embodiment insertedtherethrough is inserted into an abdominal cavity via a stomach duringmedical procedure.

FIG. 68 illustrates a manipulation procedure using a medical treatmentendoscope.

FIG. 69 is a view showing the structure of a modified example of the tipof the medical treatment endoscope according to the fourth embodiment.

FIG. 70 illustrates a manipulation procedure using the medical treatmentendoscope shown in FIG. 69.

FIG. 71 is a view showing the structure of a modified example of the tipof the medical treatment endoscope according to the fourth embodiment.

FIG. 72 is a perspective view showing a medical treatment endoscopeaccording to a fifth embodiment.

FIG. 73 is an enlarged view of an operation section.

FIG. 74 is a view taken along the line A-A in FIG. 73 in parallel withan axial direction of a first operation section.

FIG. 75 is a view on arrow AB in FIG. 74.

FIG. 76 is a cross-sectional view along the line AC-AC in FIG. 75.

FIG. 77 is a cross-sectional view along the line AD-AD in FIG. 75.

FIG. 78 is an exploded view for a rotational axis.

FIG. 79 is a perspective view for the other rotational axis, a supportchip, and a bending wire.

FIG. 80 is a cross-sectional view along the line AE-AE in FIG. 79.

FIG. 81 is a plan view illustrating a first operation stick and aprocedure instrument.

FIG. 82 is a cross-sectional view along the line AF-AF in FIG. 81illustrating a pre-insertion state of the procedure instrument.

FIG. 83 is a perspective view for a piston.

FIG. 84 is a cross-sectional view showing an enlarged state of a firstoperation stick illustrated in FIG. 77.

FIG. 85 shows an enlarged state of a channel illustrated in FIG. 84.

FIG. 86 is a plan view illustrating a procedure instrument.

FIG. 87 is a cross-sectional view along the line AG-AG in FIG. 86.

FIG. 88 describes how to attach a protection member to a ring.

FIG. 89 describes a post-attached protection member disposed to thering.

FIGS. 90A and 90B illustrate a cam in a perspective view.

FIG. 91 is a view on arrow AH in FIG. 90.

FIG. 92 is a cross-sectional view along the line AI-AI in FIG. 86.

FIG. 93 is a cross-sectional view along the line AJ-AJ in FIG. 86.

FIG. 94 illustrates motions provided by a cam, a piston, and aconnection plate when the procedure instrument is inserted into thefirst operation stick.

FIG. 95 illustrates the piston pushed up by the cam.

FIG. 96 illustrates a retractable state of the connection plate.

FIG. 97 illustrates the cam disposed between two grooves of theconnection plate.

FIG. 98 illustrates an engaged state of the cam to a second groove.

FIG. 99 illustrates the cam pushing up the piston when removing theprocedure instrument.

FIG. 100 illustrates the piston pushed up by rotating the cam.

FIG. 101 illustrates a base having an operation section joined to asecond bending slider disposed on a side of a base.

FIG. 102 is a cross-sectional view illustrating a mechanism for joiningthe second bending slider to the operation section in the configurationshown in FIG. 101.

FIG. 103 is a view showing a modified example of the cam.

FIG. 104 illustrates a feed operation for the procedure instrument.

FIG. 105 illustrates a feed operation for the procedure instrument.

FIG. 106 illustrates a combined use of the medical treatment endoscopeand an overtube.

FIG. 107 is an external view for the procedure instrument.

FIG. 108 is a cross-sectional view for the procedure instrument.

FIG. 109 is a cross-sectional view along the line AK-AK in FIG. 108.

FIG. 110 is a cross-sectional view along the line AL-AL in FIG. 108.

FIG. 111 illustrates a pusher wire protruding from a needle.

FIG. 112 illustrates a retainer embedded in tissue of an inner wall of abody cavity.

FIG. 113 illustrates a disposition of the operation section having anovercoat tube enclosing a needle.

FIG. 114 is a view showing the overcoat tube enclosing the needle.

FIG. 115 illustrates a main body of the operation section pushed intothe overcoat tube.

FIG. 116 illustrates the needle protruding into the inner wall of thebody cavity.

FIG. 117 illustrates the protruding stabbing into the inner wall of thebody cavity.

FIG. 118 illustrates a forwarded state of a slider.

FIG. 119 illustrates an anchor extruded from the needle.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments according to the present invention will now be described indetail below. Structural elements that are equivalent in the followingwill be assigned the same numeric symbols and redundant explanationsthereof will be omitted.

First Embodiment

As shown in FIGS. 1 through 3, the medical treatment endoscope 1according to this embodiment is provided with a flexible first sheath(sheath) 3 in which an open-ended first lumen 2 is formed; a secondsheath 9A having a first arm member 8A to which is disposed anopen-ended instrument insertion channel (second lumen) 6 into whichinstruments such as gripping forceps 5 are inserted, and a bending part7 that projects out from the first sheath 3 and carries out bendingactions; and a third sheath 9B having a second arm member 8B to whichthe instrument insertion channel 6 and the bending part 7 are disposed.Moreover, as shown in FIGS. 4 through 8B, the medical treatmentendoscope 1 according to this embodiment is further provided with anopen/close mechanism 10 for changing the inclination of the first armmember 8A and the second arm member 8B that project out from the firstsheath 3, from the central axis C1 of the first sheath 3 to a directionaway from the central axis C1, and from this direction away from thecentral axis C1 toward the direction of the central axis C1 (separationrelease); a viewing device 12 that is disposed at the front end side ofthe first sheath 3; and an advance/retract mechanism 13 for advancingand retracting the first arm member 8A with respect to the first sheath3.

The second sheath 9A has a front end and a base end, the front endregion forming the first arm member 8A. The second sheath 9A is insertedinto the first lumen 2 so as to project out from the first sheath 3, ata position in the first lumen 2 so as to appear on the right side of theviewing screen. The third sheath 9B has a front end and a base end, thefront end region forming the second arm member 8B. The third sheath 9Bis inserted into the first lumen 2 adjacent to the second sheath 9A, soas to project out from the first sheath 3.

As shown in FIGS. 1 and 2, rigid front end parts 15 are disposed at thefront ends of the first arm member 8A and the second arm member 8B. Abumper 15 a is provided at the front end part 15 for limiting movementin the forward direction when gripping forceps 5 or the like areinserted from the base end side of the instrument insertion channel 6.

As in the case of the typical flexible endoscope, the bending part 7 isdesigned such that a plurality of joint wheels 16 are mutually axiallysupported to enable rotation, and are connected along the direction ofthe central axis C2 of the first arm member 8A and the second arm member8B. Furthermore, bending wires 17A, 17B, 17C, and 17D such as shown inFIG. 3, are connected to the joint wheel 16A disposed farthest from thefront end. Bending wires 17A, 17B, 17C, and 17D are each inserted intoand pass through the joint wheels 16 at positions so as to divide thecircumferential periphery of the joint wheels 16 into quarters.

Bending wires 17A and 17B, and bending wires 17C and 17D are pairedrespectively, and positioned so as to be symmetrical about the center ofbending part 7. Each bending wire 17A, 17B, 17C, and 17D is insertedinto a bending wire coil 18 within the first sheath 3. A video cable 20,which is connected to a viewing device 12 which includes an imagepick-up unit 11 and an objective lens (optical member for viewing) 23,and two light guides (illuminating members) 21A and 21B which emitilluminating light onto illuminating lenses (illuminating opticalmembers) 21 a, which are structural components of the illuminatingmembers and are for lighting the object to be illuminated by forming theilluminating light bundles into a desired light bundle profile, areinserted into the first sheath 3 so as not to interfere with the secondsheath 9A, the third sheath 9B and the various bending wires. A rigidsheath front end part 3A is disposed to the front end of the firstsheath 3. An objective lens 23, and illuminating lenses 21 a which areon either side of the objective lens so as to interpose the objectivelens 23 therebetween, are disposed to the sheath front end part 3A. Inother words, the illuminating members are disposed on either side of theviewing device. As shown in FIG. 7A, a plurality of markings 22, forunderstanding the length of the inserted portion when the endoscope isinserted into the patient, are provided at predetermined intervals alongthe surface of the first sheath 3 on the hand-held side thereof.

As shown in FIGS. 1, 2A, 2B, and 10, a gripping forceps 5 is providedwith a forceps insertion part 25 that has a long narrow coil sheath 25a. A pair of forceps pieces 26A and 26B are disposed to the front end ofthe forceps insertion part 25. This pair of forceps pieces 26A and 26Bis connected to a forceps manipulating wire 27, which is inserted intothe coil sheath 25 a to enable free advancing and retracting, via aforceps linking part 28 which converts the advancing/retractingoperation of the forceps manipulating wire 27 into the opening/closingoperation of the paired forceps pieces 26A and 26B. A forceps linkingpart 28 is disposed to a front end cover 29 which is attached to thecoil sheath 25 a.

As shown in FIGS. 2A and 2B, this gripping forceps 5 is fixed in placevia a first connecting member 30A, a second connecting member 30B and athird connecting member 30C to the second arm member 8B to enable freerotation. The first connecting member 30A is tubular, with its innerperipheral surface fixed in place near the front end of the grippingforceps 5 by a screw, adhesive agent or the like. The second connectingmember 30B is in the form of a short pipe, and is interposed between thebumper 15 a of the front end part 15 and the first connecting member30A. The third connecting member 30C is in the form of a short pipe, andis formed so that the base end projects inward in the radial direction.This third connecting member 30C engages with the front end part 15, andpushes the first connecting member 30A in the forward direction. As aresult, the second connecting member 30B is pushed further forward thanthe first connecting member 30A, coming into contact with the bumper 15a of the front end part 15, thereby restricting movement of the grippingforceps 5 in the advancing or retracting direction. On the other hand,the gripping forceps 5 are attached in a freely rotating manner withrespect to the instrument insertion channel 6. Note that the thirdconnecting member 30C may also be attached to the front end part 15 byscrewing, or by an adhesive agent or the like.

The gripping forceps 5 are provided with a forceps operating part(procedure operating part) 31. The forceps operating part 31 is providedwith a forceps operating part main body 32 to which the coil sheath 25 ais connected, and a forceps handle 33 to which a forceps manipulatingwire 27 is connected and which is disposed in a freely retracting andadvancing manner with respect to the forceps operating part main body32.

The open/close mechanisms 10 are respectively provided corresponding tothe number of the first arm members 8A and the second arm members 8B.Note that since the structure is almost entirely the same, the followingexplanation will be directed to the open/close mechanism 10 of the firstarm member 8A.

As shown in FIGS. 4 through 8B, the open/close mechanism 10 is providedwith a bending opening/closing wire (open/close operating member) 35,which is capable of advancing and retracting with respect to the firstsheath 3; a linking part 36 to which the end of the bendingopening/closing wire 35 is connected, which converts theadvancing/retracting operation of the bending opening/closing wire 35into the opening/closing operation of the first arm member 8A withrespect to the first sheath 3; and a support 37 which is in the form ofa short pipe that is axially supported to enable rotation about thelinking part 36, or, alternatively, is connected to the linking part 36in a manner so as to prevent rotation. This short pipe-shaped support 37is fixed in place along the bending part 7 of the arm member 8A. Notethat it is also acceptable to fix this short pipe-shaped support 37further toward the base end than the bending part 7.

The linking part 36 is formed extending in the form of a long plate, andone end 36 a is axially supported by a guide member 42 of the firstsheath 3, explained below, to enable rotation. Note that in the case ofthe second arm member 8B, one end 36 a of the linking part 36 is axiallysupported by a sliding member 43, explained below, that can advance andretract along the central axis C1.

The support 37 is supported by another end 36 b of the linking part 36via a support axis 38, to enable rotation thereof, or alternatively, isconnected so that rotation is not possible. The other end 36 b of thelinking part 36 is formed in the shape of a disk centered about theposition of attachment to the support axis 38, with bendingopening/closing wires 35 supported by the periphery thereof. The bendingopening/closing wires 35 are disposed inside the first sheath 3,inserted into respective bending opening/closing wire coils 41.

An advance/retract mechanism 13 is provided with a guide member 42extending in the direction of the central axis C1 of the first sheath 3and fixed in place to the first sheath 3, and a sliding member 43 thatcan be freely advanced and retracted with respect to the guide member42. The guide member 42 is formed in the shape of a flat plate extendinga predetermined length in one direction, and, with respect to thecentral axis C1 of the first sheath 3, is disposed at a positionopposite where the light guides 21A and 21B and the video cable 20 areinserted (i.e., the area opposite where the light guides 21A and 21B andthe video cable 20 are inserted, such that the second sheath 9A and thethird sheath 9B are interposed therebetween). An engaging convexity 42A,approximately cylindrical in shape, is provided to one end in the widthdirection of the guide member 42 on the first arm member 8A side. Thesliding member 43 is provided with a roughly C-shaped engaging concavity43A that engages with the engaging convexity 42A to enable sliding, anda connector 43B that links the engaging concavity 43A and the first armmember 8A. The amount of movement of the sliding member 43 with respectto the guide member 42 is restricted to predetermined limits Note thatit is also acceptable to enable advancing and retracting of the secondarm member 8B, rather than the first arm member 8A, using the same typeof advance/retract mechanism.

As shown in FIGS. 9 though 12, the medical treatment endoscope 1 isprovided with an operating part 51 having a frame 45; an open/closeoperating part 46 that is connected to the base end of the bendingopening/closing wire 35 of the open/close mechanism 10, for carrying outadvancing and retracting manipulation of the bending opening/closingwire 35; a bending operating part 47, to which the forceps operatingpart 31 of the gripping forceps 5 can be attached, for advancing andretracting manipulation of the bending wires 17A, 17B, 17C, and 17D thatare connected to the respective bending parts 7 of the first arm member8A and the second arm member 8B by movement of the forceps operatingpart 31; an advance/retract operating part 48 for advancing andretracting the sliding member 43 of the advance/retract mechanism 13with respect to the guide member 42; and a rotation operating part 50for connecting the base end of the first sheath 3 to the frame 45 in amanner to enable rotation.

The frame 45 is provided with a moving frame 45A where the open/closeoperating part 46 and the bending operating part 47 of the arm member 8Aare disposed; and a fixed frame 45B where the open/close operating part46 and the bending operating part 47 of the arm member 8B, and therotation operating part 50 of the first sheath 3, are disposed. Armclamps 52 for supporting the first arm member 8A and the second armmember 8B projecting from the base end of the first sheath 3 farthertoward the hand-held side are respectively disposed along the centralaxis C3 to moving frame 45A and fixed frame 45B. In addition to thefirst arm member 8A and the second arm member 8B, the light guides 21Aand 21B and the video cable 20 project out from the base end of thefirst sheath 3, and are connected respectively to a light source deviceL and a controller C. A fixing screw 45 a for connecting and fixing inplace a scope holder 86, explained below, is disposed to the bottom ofthe fixed frame 45B. Note that with respect to fixing with the scopeholder 86, it is also acceptable to enable free sliding so that it ispossible to adjust the position of the front end of the medicaltreatment endoscope 1 inside the body cavity by advancing and retractingthe entire operating part.

The open/close operating part 46 is provided with an open/closeoperating part main body 53 and an open/close handle 55 to which thebase end of the bending opening/closing wire 35 is connected and whichcan advance and retract with respect to the open/close operating partmain body 53. The open/close operating part main body 53 is respectivelyfixed in place to the fixed frame 45B and the moving frame 45A. A rack53A is formed at the open/close operating part main body 53 forrestricting movement toward the front end side when the open/closehandle 55 is pulled toward the hand-held side. The advance of theopen/close handle 55 with respect to the open/close operating part mainbody 53 is restricted as a result of engagement of this rack 53A with agear, not shown in the figures, that is provided inside the open/closehandle 55. In this restricted state, the above-mentioned gear can bemoved away and released from the rack 53A by pressing a release button55A that is provided at the open/close handle 55. When a starting statefor the open/close mechanism 10 is defined as the state in which thefirst arm member 8A and the second arm member 8B are closed at aposition along the direction of the central axis C1 of the first sheath3, then, in this starting state, the open/close handle 55 is set so asto be positioned toward the front end of the open/close operating partmain body 53.

The bending operating part 47 is provided with a vertical bendingoperating part 56 for moving bending part 7 in the vertical direction,for example; a horizontal bending operating part 57 for moving thebending part 7 in a direction perpendicular to the aforementioned, i.e.,moving the bending part 7 in the horizontal direction, for example; andan attachment part 58 for attaching the forceps operating part main body32 of the forceps operating part 31 in a manner so as to enable itsrotation. The attachment part 58 is connected to enable movement in therespective directions inside the each of the frames at the area ofintersection between a first movement restricting member 60, which is inthe form of a rectangular frame provided for causing relativedisplacement of the attachment part 58 in the horizontal direction only,and a second movement restricting member 61, which is in the form of arectangular frame disposed perpendicular to the first movementrestricting member 60 and provided for causing relative displacement ofthe attachment part 58 in the vertical direction only. Note that thebending operating parts 47 are disposed to each of the first arm member8A and the second arm member 8B.

A vertical bending operating part 56 is provided with a pair ofrod-shaped first bending guides 62A and 62B in which the longitudinalends of the first movement restricting member 60 are engaged in a mannerto enable sliding, in order to cause parallel displacement of the firstmovement restricting member 60 in the vertical direction; a first diepart 63 that is connected to the end 60 a of the first movementrestricting member 60, and moves along the first bending guide 62A; afirst belt member 65, in which both ends are connected to the first diepart 63 so as to be in opposition to one another from the directionalong the first bending guide 62A; two adjusting wheels 66 for adjustingthe tension by winding the first belt member 65; a first chain belt 67in which the bases of the bending wires 17A and 17B are connected ateither end; and a first gear 68 having a small diameter part 68 b inwhich the first chain belt 67 engages and a large diameter part 68 aaround which the first belt member 65 is wound.

The horizontal bending operating part 57 is provided with the sameconstruction as the vertical bending operating part 56. In other words,the horizontal bending operating part 57 is equipped with a pair ofrod-shaped second bending guides 70A and 70B in which the longitudinalends of the second movement restricting member 61 are engaged in amanner to enable sliding, in order to cause parallel displacement of thesecond movement restricting member 61 in the horizontal direction; asecond die part 71 that is connected to the end 61 a of the secondmovement restricting member 61, and moves along the second bending guide70A; a second belt member 72, in which both ends are connected withrespect to the second die part 71 so as to be in opposition to oneanother from the direction along the second bending guide 70A; adjustingwheels 66 for adjusting the tension by winding the second belt member72; a second chain belt, not shown in the figures, in which the bases ofthe bending wires 17C and 17D are connected at either end; and a secondgear 75 in which the second chain belt engages and around which thesecond belt member 72 is wound.

The advance/retract operating part 48 is provided with a slide rail 76for moving the moving frame 45A, to which the open/close operating part46 and the bending operating part 47 connected to the arm member 8A aredisposed, with respect to the fixed frame 45B; and a base 77 which isdisposed to the moving frame 45A and engages in a sliding manner withthe slide rail 76. An advance/retract restricting member 78 is disposedto the front end side of the slide rail 76. The amount of sliding of themoving frame 45A is restricted to a predetermined range as a result ofthe base 77 coming into contact with this advance/retract restrictingmember 78. This advance/retract restricting member 78 is positioned at apredetermined location so that the sliding member 43 of theadvance/retract mechanism 13 does not come free from the guide member42.

The rotation operating part 50 is disposed further toward the front endside of the frame 45 than the arm clamp 52, and is provided with asheath connector 82, to which a rotation knob 81 is disposed and thebase end of the first sheath 3 is connected; and a rotation support 83for supporting the sheath connector 82 in a manner to enable rotation. Ascrew hole 83 a is formed in the rotation support 83, and a through-hole82 a is formed in the sheath connector 82. The rotation of the sheathconnector 82 with respect to the rotation support 83 is restricted as aresult of the engagement of a stopping screw or the like at the positionwhere the screw hole 83 a and the through-hole 82 a are overlapped. Theamount of rotation is preferably on the order of 180 degrees to eitherside. Note that a through-hole 83 b is disposed to the rotation support83 for insertion of the light guides 21A and 21B and the video cable 20.

Next, the operation of the embodiment of the present invention will beexplained.

When opening the first arm member 8A and the second arm member 8B withrespect to the first sheath 3 from the starting state shown in FIGS. 5Aand 7A, the open/close handle 55 is slid with respect to the open/closeoperating part main body 53 a predetermined distance toward thehand-held side. The bending opening/closing wire 35 is thus retractedwith respect to the first sheath 3 toward the hand-held side.Accompanying this, the other end 36 b of the linking part 36 receives arotational torque toward the base end side of the first sheath 3. Theother end 36 b side of the linking part 36 is rotated about the one end36 a by a predetermined angle in the direction away from the centralaxis C1 of the first sheath 3. As shown in FIGS. 6A and 8A, the support37 rotates with respect to the first sheath 3, and opens. In this case,the position of the open/close handle 55 is fixed in place by the rack53A of open/close operating part main body 53, and the position of thebending opening/closing wire 35 is thus fixed in place with respect tothe first sheath 3.

When closing the first arm member 8A and the second arm member 8B withrespect to the first sheath 3, the open/close handle 55 is advancedforward with respect to the open/close operating part main body 53,while pressing on the release button 55A of the open/close handle 55. Atthis time, the bending opening/closing wire 35 is advanced forward withrespect to the front end side of the first sheath 3. Accompanying this,the rotational torque applied on the linking part 36 is released, andthe other end 36 b of the linking part 36 is rotated about the one end36 a of the linking part 36 in a direction toward the central axis C1 ofthe first sheath 3. As a result, the support 37 rotates with respect tothe first sheath 3 and closes, i.e., resumes the starting state.

The moving frame 45A of the operating part 51 is advanced with respectto the fixed frame 45B, from the starting state shown in FIGS. 5A and7A, when moving the first arm member 8A further toward the front endside of the first sheath 3. At this time, the base 77 advances along theslide rail 76, while the sliding member 43 of the open/close mechanism10 moves forward with respect to the guide member 42. In this case, theentirety of the moving frame 45A moves, so that both the bendingoperating part 47 and the open/close operating part 46 move.Accordingly, there is no change in the open/close state and the bendingstate of the first arm member 8A. In this way, as shown in FIGS. 14 and15, the first arm member 8A enters a state where it is advanced withrespect to the first sheath 3.

In contrast, the moving frame 45A of the operating part 51 is retractedwith respect to the fixed frame 45B when moving the first arm member 8Atoward the hand-held side of the first sheath 3. At this time, the base77 is retracted along the slide rail 76, while the sliding member 43 ofthe open/close mechanism 10 is retracted with respect to the guidemember 42. As a result, the first arm member 8A is again disposed at thestarting state position.

When bending the first arm member 8A and the second arm member 8B in thevertical direction, the vertical bending operating part 56 ismanipulated. In other words, the forceps operating part 31 which isattached to the attachment part 58 is gripped and moved in the verticaldirection. In this case, the attachment part 58 moves vertically withinthe limits of the second movement restricting member 61, while at thesame time, the first movement restricting member 60 moves together withthe attachment part 58 along the paired first bending guides 62A and62B. Here, the first die part 63 also moves in the vertical direction,so that the first belt member 65 moves accompanying this, and the firstgear 68 is rotated in either direction. At this time, the first chainbelt 67 is rotated in either direction, and, accompanying this, one ofthe bending wires 17A and 17B is advanced with respect to the firstsheath 3, while the other is retracted. In this way, the joint wheels 16of the bending part 7 are inclined accompanying the movement of thebending wires 17A and 17B, and bend vertically.

In contrast, when bending the first arm member 8A and the second armmember 8B in the horizontal direction, the horizontal bending operatingpart 57 is manipulated. In other words, the forceps operating part 31which is attached to the attachment part 58 is gripped and moved in thehorizontal direction. In this case, the attachment part 58 moveshorizontally within the limits of the first movement restricting member60, while at the same time, the second movement restricting member 61moves together with the attachment part 58 along the paired secondbending guides 70A and 70B. Here, the second die part 71 also moves inthe horizontal direction, so that the second belt member 72 movesaccompanying this, and the second gear 75 is rotated in eitherdirection. At this time, the second chain belt 73 is rotated in eitherdirection, and, accompanying this, one of the bending wires 17C and 17Dis advanced with respect to the first sheath 3, while the other isretracted. In this way, the joint wheels 16 of the bending part 7 areinclined accompanying the movement of the bending wires 17C and 17D, andbend horizontally.

When rotating the first sheath 3 with respect to the operating part 51,the rotation knob 81 of the rotation operating part 50 is gripped androtated in the desired direction. As a result, the sheath connector 83rotates relative to the rotation support 82, causing the first sheath 3to rotate in the desired direction relative to operating part 51.

Next, an explanation will be made with reference to FIGS. 18 through 20of an operative procedure performed via a natural orifice using themedical treatment endoscope 1. Note that the following explanationconcerns the technique of inserting the medical treatment endoscope 1from the mouth M of a patient PT into the stomach ST, opening a hole inthe wall of the stomach, and then carrying out a procedure by insertingthe first sheath 3 of the medical procedure endoscope 1 into theabdominal cavity AC. In the case of the present embodiments, apredetermined procedure is performed by inserting a high frequency knife85 into the first arm member 8A, and a gripping forceps 85 into thesecond arm member 8B.

The patient PT is placed on his/her back, and a typical endoscope 1A isintroduced into the open-ended lumen 88 of an over-tube 90 from the baseend 91 of the over-tube 90. This open-ended lumen 88 extends along theaxial direction of the over-tube 90. The over-tube 90 is then insertedfrom the mouth M of the patient PT into the esophagus ES, and positionedin the stomach ST as shown in FIG. 18.

Next, the stomach ST is inflated by relaying air into it, after which anopening SO is formed in the stomach wall by excision. The insertion part92 of the over-tube 90 and the endoscope 1A are introduced into theabdominal cavity AC via the opening SO. Next, the endoscope 1A iswithdrawn from the over-tube 90, and the first sheath 3 of the medicaltreatment endoscope 1 is inserted in its place into the lumen 88 of theover-tube 90, so as to project out from the front end of the over-tube90.

As an example here, the case will be explained where a high-frequencyknife 85 is inserted into the second sheath 9A and the first arm member8A. First, the high-frequency knife 85 is inserted into the instrumentinsertion channel 6, and the front end of the high-frequency knife 85comes into contact with the bumper 15 a that is provided at the frontend part 15 of the first arm member 8A. The front end of thehigh-frequency knife 85 is urged toward the bumper 15 a by pushing thehigh-frequency knife 85 further in from the base end side, so that theknife operating part, not shown, of the high-frequency knife attachesinto the attachment part 58 of the operating part 51. In this way,advancing and retracting of the high-frequency knife 85 with respect tothe first arm member 8A is restricted. Note that the high-frequencyknife 85 is supported to enable free rotation with respect to the firstarm member 8A and the operating part 51.

As shown in FIG. 19, the operating part 51 of the medical treatmentendoscope 1 is mounted in a manner to enable sliding to a mount 87 thatis disposed at a scope holder 86 which is attached to a bed not shown inthe figures.

After positioning, the operations of opening/closing, bending, andadvancing/retracting of the first arm member 8A and the second armmember 8B are carried out according to the desired procedures, toperform a predetermined procedure, as shown in FIG. 20. After theprocedure is carried out, the medical treatment endoscope 1 is withdrawnback into the stomach ST from the opening SO in the stomach wall, andthen removed from the mouth M of the patient PT.

For example, a case for gallbladder extraction will be explained.

A cervical part or bottom part of a gallbladder is grasped and retractedwith a grasping forceps 5 inserted through the second arm member 8B toexpose a Calot trigone.

The serous membrane of the cervical part of the gallbladder is excised alittle at a time with a high frequency knife 85 inserted through thefirst arm member 8A. A retracting direction exerted by the graspingforceps 5 inserted through a second arm member 8B is adjusted in orderto apply appropriate tensions to the excised part. Meanwhile, adiposetissue and fiber tissue including the serous membrane are peeled withthe high frequency knife 85 from the cervical part of the gallbladder tothe cystic duct.

After identifying the cystic duct, the periphery is totally peeled.Similarly, arteria cystica is identified and its periphery is totallypeeled. Consequently, the treatment instruments used in the first armmember 8A are exchanged for a clip, which is not shown in the drawings,and the cystic duct in the vicinity of the cervical part of thegallbladder is clipped.

After replacing the treatment instruments at the first arm member 8Awith the high frequency knife 85 or a pair of scissors which is notshown in the drawings, a half of the cystic duct is incised so as toobserve bile outflow. Consequently, the treatment instruments used inthe first arm member 8A are exchanged for an imaging tube, which isinserted into the cystic duct. After confirming the absence of a stonein the bile duct, the clip is re-applied to the first arm member 8A todouble-clip the bile duct. The clip at the first arm member 8A isreplaced by the high frequency knife 85 to incise the cystic duct.

A portion in the vicinity of the gallbladder and two portions in thevicinity of the nerve center are clipped by a similar method of incisingthe arteria cystica and the cystic duct. The arteria cystica is thusincised. The margin of the cystic duct is grasped and retracted by thegrasping forceps 5 at the second arm member 8B, and the gallbladder ispeeled from a gallbladder bed by operating the high frequency knife 85attached to the first arm member 8A.

While grasping the gallbladder between the grasping forceps attached tothe second arm member 8B, the medical treatment endoscope 1 is extractedfrom the overtube 90 to take out the liberated gallbladder. In the caseof a somewhat a larger gallbladder, the bile in the gallbladder may besucked into a smaller volume with a hollow needle which is not shown inthe drawings. In addition, prior to taking out the gallbladder from thebody, the medical treatment endoscope 1 may be extracted from theovertube 90, and an organ-container pouch, not shown in the drawings,grasped by the grasping forceps 5 attached to the second arm member 8Bmay be reinserted to contain the gallbladder.

In addition to the previously explained gallbladder extraction, themedical treatment endoscope according to the present invention can beused for various manipulations, e.g., appendectomy, gastroduodenalbypass, liver biopsy, biopsy of the pancreas, tubal interruption, andhysterectomy. After the abdominal cavity having been treated is suitablyirrigated, the medical treatment endoscope 1 is retracted into thestomach ST via the wall of the opening SO. After releasing the pressureapplied to the abdominal cavity AC, the medical treatment endoscope 1 istaken out of the mouth M of the patient PT.

The opening SO formed on the wall of the stomach is sutured, and theovertube 90 and the medical treatment endoscope 1 are subsequentlyextracted from the patient; thus, the manipulation is completed.

According to the medical treatment endoscope 1, the open/close mechanism10 can be used to move the central axis C1 of the first arm member 8Aand the second arm member 8B, which are respectively inserted into thefirst lumen 2 of the first sheath 3, away from the central axis C1 ofthe first sheath 3, further bending the bending part 7 of the first armmember 8A and the second arm member 8B. As a result, even if aninstrument device such as the gripping forceps 5 is inserted into theinstrument insertion channel 6, the hand-held side of the first armmember 8A and the second arm member 8B bend with respect to the frontend side of the first sheath 3. Thus, the inclination of the instrumentdevice can be deviated from the line of vision V of the image pick-upunit 11 that is disposed to the sheath front end part 3A of the firstsheath 3. Accordingly, it is possible to visually confirm the front endside of the first arm member 8A and the second arm member 8B withsufficient confirmation of the line of vision V of the image pick-upunit 11. As a result, the medical procedure can be carried out safelyand assuredly.

In this case, the axial force generated by advancing and retracting thebending opening/closing wire 35 with respect to the first sheath 3 canbe converted through the linking part 36 of the open/close mechanism 10into the force for opening and closing the first arm member 8A and thesecond arm member 8B. As a result, the first arm member 8A and thesecond arm member 8B can be opened or closed with respect to the centralaxis C1 of the first sheath 3. In particular, when opening the first armmember 8A and the second arm member 8B, the bending opening/closing wire35 is pulled toward the hand-held side. Accordingly, it is possible toadjust the transmission of force to the bending part 7, and to finelyadjust the opening angle of the first sheath 3 with respect to thecentral axis C1. In addition, in the case where it has been designedthat the first arm member 8A and the second arm member 8B will have asuitable angle of opening with respect to the central axis C1 by meansof at once pulling the open/close handle 55 toward the hand-held sideuntil it comes into contract with the open/close operating part mainbody 53, it is possible to simplify the open/close operation of thefirst arm member 8A and the second arm member 8B.

In addition, it is possible to operate the open/close mechanism 10 byoperating the open/close operating part 46 of the operating part 51 toadvance and retract the bending opening/closing wire 35 with respect tothe first sheath 3. In addition, by performing operations with theforceps operating part 31 for the gripping forceps 5 in a state ofattachment to the bending operating part 47, it is possible to carry outnot only the opening/closing operation of the pair of forceps pieces 26Aand 26B of the gripping forceps 5, but also carry out the bendingoperation of the bending part 7, thus facilitating the procedure.

Furthermore, by sliding the moving frame 45A with respect to the fixedframe 45B in the advance/retract operating part 48, it is possible tocarry out the advance/retract operation of the first arm member 8A andthe second arm member 8B with respect to the first sheath 3 by advancingor retracting the sliding member 43 with respect to the guide member 42.Accordingly, the treatment scope of the gripping forceps 5 with respectto the first sheath 3 can be expanded.

Furthermore, by rotating the rotation knob 81 of the rotation operatingpart 50, the first sheath 3 can be rotated along with the first armmember 8A and the second arm member 8B from the base end side of thefirst sheath 3, and the opening/closing direction of the first armmember 8A and the second arm member 8B with respect to the first sheath3 can be changed. Note that when it is desired to rotate a singleinstrument, then rotation to the desired state can be achieved byrotating the forceps operating part 31 with respect to the attachmentpart 58.

Because it is possible to use the support 37 of the open/close mechanismto support the first arm member 8A and the second arm member 8B farthertoward the base end side than the bending part 7, the entirety of thebending part 7 can be used in the bending action, regardless of whetherperforming the open/close operation or the bending operation. Thus, thedegree of freedom of the arm can be improved. Conversely, when thesupport 37 is provided along the bending part 7, the degree of freedomof each of the arm members is decreased, however, a greater force can bedelivered. In addition, by manipulating the bending part 7 of the firstarm member 8A and the second arm member 8B, which has a larger diameterthan the diameter of the instrument insertion channel 6, the instrumentcan be more easily bent, and the procedure performed, than in the casewhere inserting a single instrument having bending capabilities throughthe instrument insertion channel 6 and then bending the instrument.

In addition, since the bending part 7 is employed only for bending aninstrument such as the gripping forceps 5 or the like, it is possible toachieve greater bending, and output a greater force, as compared to adesign that requires bending of a plurality of objects such asinstruments, video cables (image guides in optical endoscopes), lightguides and the like, such as seen in conventional endoscopes.

Second Embodiment

A second embodiment will now be explained with reference to the figures.

The second embodiment differs from the first embodiment with respect tothe point that both the first arm member 8A and the second arm member 8Bof a medical treatment endoscope 100 according to this embodiment aredesigned to advance and retract with respect a sheath 101.

Namely, as shown in FIG. 21, roughly cylindrical engaging convexities103A are disposed at either end of a guide member 103 for anadvance/retract mechanism 102, along the width direction of the guidemember 103. The first arm member 8A and the second arm member 8B areconnected to a sliding member 105 that has an engaging concavity 105Afor engaging in a freely sliding manner with the engaging convexities103A via a connector 105B.

As in the case of the moving frame 45A of the operating part 51according to the first embodiment, this operating part is designed sothat the open/close operating part 46 and the bending operating part 47of not only the first arm member 8A, but also the second arm member 8B,are capable of movement with respect to the fixed frame.

Next, the effects of this embodiment will be explained. Note that thecase when opening and closing the first arm member 8A and the second armmember 8B with respect to the sheath 101, the case when bending thefirst arm member 8A and the second arm member 8B, and the case whenrotating the sheath 101, provide the same effects as those of the firstembodiment.

The case when advancing or retracting the first arm member 8A and thesecond arm member 8B with respect to the sheath 101, as well, providesthe same effects as in the case when advancing or retracting the firstarm member 8A with respect to the fixed frame 45B in the firstembodiment. In other words, when moving both the first arm member 8A andthe second arm member 8B farther toward the front end side of the sheath101, each of the moving frames of the operating part to which the firstarm member 8A and the second arm member 8B are respectively connected isadvanced with respect to the fixed frame. At this time, as in the firstembodiment, the base at the operating part is advanced along the sliderail, while the sliding members 105 of the advance/retract mechanism 102each advance with respect to the guide member 103. In this way, thefirst arm member 8A and the second arm member 8B are advanced withrespect to the sheath 101.

On the other hand, when moving the first arm member 8A and the secondarm member 8B toward the hand-held side of the sheath 101, therespective moving frames are retracted with respect to the fixed frame.At this time, the base is retracted along the slide rail, while thesliding members 105 are retracted with respect to the guide member 103.In this way, the first arm member 8A and the second arm member 8B areonce again disposed at the starting state position.

The medical treatment endoscope 100 of this embodiment offers the sameactions and effects as described in the first embodiment. In particular,since the first arm member 8A and the second arm member 8B are advancedand retracted with respect to the sheath 101, it is possible to ensure awider line of vision V for the image pick-up unit 11. Furthermore, theapproach angle for instruments such as gripping forceps and the like canbe adjusted to a more suitable position. In addition, it is possible toincrease the operating stroke for the gripping forceps, etc.

The technical scope of the present invention is not limited to theembodiments described above. Rather, various modifications may be addedprovided that they do not depart from the spirit of the invention.

For example, the arm members are not limited to two; rather, three ormore arm members may be provided. It is also acceptable to design thefront end of the second arm member so as to enable relative displacementof the gripping forceps in the advancing/retracting direction withrespect to the second arm member. In addition, while an illuminatingmember for radiating illuminating light on the target object was formedusing the light guides 21A and 21B and an illuminating lens 21 a, it isalso acceptable to provide an illuminating member by disposing a lightemitting element, an LED for example, to the sheath front end part 3A.

Third Embodiment

An eighth embodiment will now be explained with reference to thefigures. The medical treatment endoscope according to this embodimentrepresents a further improvement over the medical treatment endoscopeaccording to the first embodiment.

As shown in FIG. 22, and similar to the medical treatment endoscope 1according to the first embodiment, a medical treatment endoscope 200 isprovided with a first arm member 208A and a second arm member 208B thatcan be opened and closed. Instruments are provided at the front endparts of these first and second arm members 208A and 208B. FIGS. 22through 25 are views showing the front end part of the endoscope in thecase where the arm members 208A and 208B are spread open. FIGS. 26through 29 are views showing the front end part of the endoscope in thecase where the arm members 208A, 208B are closed. Note that in FIGS. 23through 28, the bending parts 203B and 207 are shown with the jointwheels 201 and 216 that form these bending parts 203B and 207 covered bycover members.

The medical treatment endoscope 200 according to this embodiment isprovided with a first sheath 203 having flexibility, a sheath front endpart 203A having rigidity which is provided at the front end of thefirst sheath 203, and a bending part 203B that is provided at a base endof the sheath front end part 203A. Openings are provided at front endsof the first sheath 203 and the bending part 203B. As shown in FIGS. 30and 31, these openings form a first lumen 202 through which the firstarm member 208A (a second sheath), the second arm member 208B (a thirdsheath), a video cable 220 and the like, are inserted. Furthermore, thesheath front end part 203A which is provided at the open end of thebending part 203B has an opening 203 a through which the first armmember 208A and the second arm member 208B are respectively passed.

As in the case of the typical flexible endoscope, the bending part 203Bis constructed such that a plurality of joint wheels 201 are continuousalong the direction of the central axis of the first sheath 203 and areaxially supported to enable mutual rotation, and four bending wires 201Bare connected to the most distal joint wheel 201A and extend along theinside of the bending part 203B. These four bending wires 201B are eachpassed through the joint wheels 201 at positions so as to divide acircumferential periphery of the joint wheels 201 into quarters, and arepassed through a bending wire coil that is provided inside the firstsheath 203.

As shown in FIG. 31, the first arm member 208A and the second arm member208B are provided at the sheath front end part 203A. An instrumentinsertion channel (a second lumen) 206, through which instruments suchas gripping forceps 205B are inserted and which is open at the distalend, and a bending part 207, which projects out from the sheath frontend part 203A and carries out bending operations, are disposed at eachof these arm members 208A and 208B respectively. Openings 203 a forenabling advance of the bending parts 207 in the lateral direction areprovided on each side of the sheath front end part 203A where the firstarm member 208A and the second arm member 208B are disposed. The bendingpart 207 is equipped with the same structure as the bending part 7 shownin FIG. 1. Namely, a plurality of joint wheels 216 are mutually axiallysupported to enable rotation, and are connected along the direction ofthe central axes of the first arm member 208A and the second arm member208B. Furthermore, as in the case of the preceding bending part 7,bending wires 117A, 117B, 117C, and 117D extended along the inside ofthe bending part 207 are connected to the joint wheel 216 that isdisposed farthest toward the front end. The bending wires 117A, 117B,117C, and 117D are each inserted into and pass through the joint wheels216 at positions so as to divide a circumferential periphery of thejoint wheels 216 into quarters.

A tubular front end part 215A is attached to the front end of thebending part 207 of the first arm member 208A. The front end part 215Ahaving an opening communicates with the instrument insertion channel206. A high-frequency scalpel 205A projects out from the open end of thefront end part 215A. And a gripping forceps 205B projects out from theopen end of the front end part 215B that is attached to the second armmember 208B. The base ends of the high-frequency scalpel 205A and thegripping forceps 205B are connected to an instrument insertion part 125which is inserted inside the instrument insertion channel 206. Thehigh-frequency scalpel 205A is provided with a needle-shapedhigh-frequency knife 224 at its end that is capable of impressing highfrequency power. The gripping forceps 205B has the same construction asthe gripping forceps 5 according to the preceding first embodiment, andis provided with a pair of forceps pieces 226A and 226B capable ofopening and closing operations via a forceps linking part 228.

In the case of this embodiment, the high frequency scalpel 205A and thegripping forceps 205B are not restricted from advancing and retractingat the front end parts 215A and 215B. Accordingly, the high frequencyscalpel 205A and the gripping forceps 205B can be advanced and retractedwith respect to the front end parts 215A and 215B by theadvancing/retracting operation of the instrument insertion part 125 thatis inserted into the instrument insertion channel 206. According to thismechanism, instruments such as the high-frequency scalpel 205A, grippingforceps 205B, etc. can be advanced or retracted with respect to anaffected part regardless of the bending state of the first arm member208A and the second arm member 208B.

As shown in FIGS. 23 through 25, an open/close mechanism 210 for movingthe first arm member 208A and the second arm member 208B in thedirections that cause them to mutually separate or to mutually comecloser together, and a viewing device 212, are provided at the sheathfront end part 203A.

As shown in FIGS. 22, 23 and 25, the open/close mechanism 210 isprovided with an open/close operating part 243 (a portion of which hasbeen omitted in FIG. 22 to facilitate viewing of the figure), which iscapable of advancing and retracting with respect to the first sheath203; a sliding member 242 which supports the open/close operating part243 and slides inside the sheath front end part 203A; two linking parts236 to which the open/close operating part 243 is connected; and asupport 237 which is connected to each of the linking parts 236 while atthe same time supporting the first arm member 208A and the second armmember 208B.

The linking part 236 is formed as a plate-shaped member, the thicknessand width dimensions thereof being determined so as to obtain thedesired rigidity. The support 237 is constructed so that its base endside is supported to enable free rotation about a support axis 240 atthe sheath front end part 203A, and to grip the first arm member 208Awith link-shaped gripping members 237 a that are provided at its frontend side. In this way, both the first arm member 208A and the second armmember 208B are fixed in place by the gripping parts 237 a of thesupports 237 extending from the sheath front end part 203A, and cannotadvance or retract with respect to the first sheath 203. An opening 203b is formed in the sheath front end part 203A that supports the base endside of the supports 237, for enabling advance of the supports 237 inthe lateral direction.

One end 236 a of the linking part 236 is supported to enable freerotation about a support axis 238 at the front end of the open/closeoperating part 243, and the other end is supported to enable freerotation about a support axis 239 of the gripping part 237 a. A frontend of the open/close operating part 243 that is connected to the oneend 236 a of the linking part 236 is positioned farther toward the frontend of the arm members 208A and 208B than the other end 236 b of thelinking member 236 that is connected to support 237. In other words, theconstruction is provided in which the two linking parts 236 and the twosupports 237 form a pantograph structure at the front end of the firstsheath 203, and modification of this pantograph structure is carried outby advance and retraction of the open/close operating part 243, therebypushing apart or pulling closed the first arm member 208A and the secondarm member 208B.

As shown in FIGS. 22 and 30, the open/close operating part 243 isinserted into the sliding member 242, and is fixed in place to theportion of the bending opening/closing wire 244, which is fixed inplace, that projects out from the front end of the sliding member 242.As shown in FIG. 30, the bending opening/closing wire 244 is insertedinto a bending opening/closing wire coil 244A that is disposed insidethe first sheath 203. As shown in FIG. 24A, the open/close operatingpart 243 is disposed to an opposite side from the viewing device 212,interposing the first arm member 208A and the second arm member 208Btherebetween. The open/close operating part 243 is disposed closer tothe central axis of the first sheath 203 than to the central axis of thefirst arm member 208A and the second arm member 208B.

As shown in FIGS. 24A and 30, the viewing device 212 is provided with animage pick-up unit 211 and two illuminating members 221A and 221B whichare disposed on either side of the image pick-up unit 211. The imagepick-up unit 211 is provided with an objective lens (optical member forviewing) 223 that is disposed at the front end surface of the sheathfront end part 203A, and is connected to a video cable 220 that isinserted into the first sheath 203. The illuminating members 221A and221B include an illuminating lens (optical member for illumination) thatis disposed lateral to the objective lens 223. The objective lens 223and the illuminating lens are disposed farther toward the front end ofthe bending part 207 than the position where the base end of the bendingpart 207 is fixed in place to the sheath front end part 203A.

Next, the operating part of the medical treatment endoscope 200 will beexplained. As shown in FIGS. 32 through 36, this medical treatmentendoscope 200 is provided with an operating part 151 that has a frame145, which includes a moving frame 145A and a fixed frame 145B, and amount 187 on which the frame 145 is mounted. The moving frame 145A andthe fixed frame 145B are connected to the mount 187 via a slidemechanism 190 that is provided at their respective underbodies. Theslide mechanism 190 includes slide rails 198 a that are provided at amount 187 side of base wall members 190 a of the moving frame 145A andthe fixed frame 145B, and a slide block 198 b that is provided at theframe 45 side of the mount 187 and engages with the two slide rails 198a in a manner that enables sliding. The moving frame 145A and the fixedframe 145B are connected via a sliding mechanism 148 in which a sliderail 148 a, provided at a lateral surface of the fixed frame 145B, and aslide block 148 b, provided at a lateral surface of the moving frame145A, engage in a manner to enable sliding. The slide rail 148 a isdisposed parallel to the slide rail 198 a of the slide mechanism 190.

The moving frame 145A and the fixed frame 145B are each provided withthe slide mechanism 190, and are connected via the slide mechanism 148.As a result, the moving frame 145A and the fixed frame 145B can both bemade to slide with respect to the mount 187. However, in the case ofthis embodiment, the base wall member 190 a of the fixed frame 145B isfixed to the mount 187, and only the moving frame 145A is able to slidewith respect to the fixed frame 145B and the mount 187 via the slidemechanisms 148 and 198.

The moving frame 145A is provided with a bending operating part 147 forcarrying out bending operation of the first arm member 208A. Theinstrument operating part 131A of the high frequency scalpel 205A can beattached to and released from this bending operating part 147. On theother hand, the fixed frame 145B is provided with an open/closeoperating part 146 for operating the open/close mechanism 210; a bendingoperating part 147 for carrying out bending operation of the second armmember 208B; a sheath operating part 194 for carrying out bendingoperation of the bending part 203B; a rotation operating part 150 whichconnects the base end of the first sheath 203 to the frame 145 in amanner to enable free rotation; a first arm clamp 152A for supportingthe first arm member 208A that extends out from the base end of thefirst sheath 203; a sheath advance/retract part 191 that is connected onthe side of the first arm clamp 152A that is opposite the rotationoperating part 150; and a second arm clamp 152B for supporting thesecond arm member 208B that extends out from the base end of the firstsheath 203. Note that while a plurality of sheaths and wires are pulledaround the operating part 151 of the medical treatment endoscope 200shown in FIGS. 32 through 36, these are shown in FIG. 34, but omittedfrom the other figures for easier review of these drawings.

Respective bending operating parts 147 are provided corresponding to thefirst arm member 208A and the second arm member 208B. The bendingoperating part 147 is provided with a roughly rectangular frame member170; a vertical bending operating part 156 for moving the bending part207 in a vertical direction, for example; a horizontal bending operatingpart 157 for moving the bending part 207 in a direction perpendicular tothe moving direction of the vertical bending operating part 156, i.e., ahorizontal direction, for example; and an attachment part 158 forattaching the instrument operating parts 131A and 131B in a manner so asto enable rotation. The attachment part 158 is constructed such that thetwo slide blocks 158A and 158B are disposed opposite one another, and soas to be fixed in place by a tubular member 193 which passes throughthese slide blocks 158A and 158B. The slide block 158A is constructed tobe able to slide in the horizontal direction after engaging with the twoslide rails 160 a that form the first movement restricting member 160which is provided to permit relative displacement of the attachment part158 in the horizontal direction only. The slide block 158B isconstructed to be able to slide in the vertical direction after engagingwith the two slide rails that form the second movement restrictingmember 161 which is provided to permit relative displacement of theattachment part 158 in the vertical direction only.

The instrument operating parts 131A and 131B are provided with aninstrument operating part main body 132 to which the instrumentinsertion part 125 is connected, and an instrument handle 133 which isdisposed to freely advance and retract with respect to the instrumentoperating part main body 132.

The vertical bending operating part 156 is provided with first bendingguides 196 for causing relative displacement of the first movementrestricting member 160 in the vertical direction; a first belt member165 connected to first die parts 160 b that are provided at the centeralong the longitudinal direction of the two slide rails 160 a that formthe first movement restricting member 160; four adjusting wheels 166 foradjusting the tension by winding the first belt member 165; a first gear168 that is connected to the first belt member 165; and a first chainbelt 167 which is connected to the first gear 168.

The first bending guide 196 is provided with two slide rails 196 a thatare equipped at the frame body of the frame member 170, and slide blocks196 b that engage with the two slide rails 196 a respectively in amanner to enable sliding, and which are connected at either end of thetwo slide rails 160 a of the first movement restricting member 160.

The ends of the first belt member 165 are each connected to the firstdie parts 160 b via four adjusting wheels 166. The first chain belt 167and the first gear 168 are attached to a plate-shaped gear box 156 a, asshown in FIG. 42. The large diameter parts 168A of the first gear 168that are connected to the first belt member 165 are attached to onesurface side of the gear box 156 a, and the small diameter parts 168B,which have the same axes as the large diameter parts 168A, are disposedinside grooves 156 b that are formed in the other surface side of thegear box 156 a. The first belt member 165 is fixed in place at the outerperipheral surface of the large diameter parts 168A. When the firstmovement restricting member 160 moves due to an operational input at thebending operating part 131, the first belt member 165 is pulled in onedirection accompanying this, and the large diameter parts 168A begin torotate. The first chain belt 167 which is housed inside the groove 156 bengages with the small diameter part 168B. The bending wires 117A and117B which extend from the first sheath 203 are each connected to an endof the first chain belt 167.

In the case of this embodiment, three sets of grooves 156 b for housingthe first chain belt 167 and the small diameter parts 168B in the gearbox 156 a are prepared. By pairing these with the different diameterlarge diameter parts 168A, it is possible to select a reduction gearratio at the vertical bending operating part 156. This reduction gearratio is determined based on a force required at the bending part 207which performs the bending operation through bending wires 117A and117B, and a force required for an operation of the bending operatingpart 147, these required forces being values that can be known inadvance.

The horizontal bending operating part 157 is provided with the sameconstruction as the vertical bending operating part 156. In other words,the horizontal bending operating part 157 is provided with secondbending guides 197 that are connected to two ends of a longitudinaldirection of the second movement restricting member 161 for causingmovement of the second movement restricting member 161 in the horizontaldirection; a second belt member 172 connected to second die parts 161 bthat are respectively provided at the center along the longitudinaldirection of the two slide rails 161 a that form the second movementrestricting member 161; four adjusting wheels 166 for adjusting thetension by winding of the second belt member 172; a second gear 175 thatis connected to the second belt member 172; and a second chain belt 173.

The second bending guide 197 is provided with two slide rails 197 a thatare provided at the frame body of the frame member 170, and slide blocks197 b that engage with the two slide rails 197 a respectively in amanner to enable sliding, and which are connected at either end of thetwo slide rails 161 a of the second movement restricting member 161.

Each end of the second belt member 172 is connected to the second dieparts 161 b via four adjusting wheels 166. The second chain belt 173 andthe second gear 175 are attached to a plate-shaped gear box 157 a, asshown in FIG. 43. Large diameter parts 175A of the second gear 175 whichare connected to the second belt member 172 are attached on one surfaceside of the gear box 157 a, and small diameter parts 175B, which havethe same axes as the large diameter parts 175A, are disposed insidegrooves 157 b that are formed in the other surface side of the gear box157 a. The second belt member 172 is fixed in place at the outerperipheral surface of the large diameter parts 175A. When the secondmovement restricting member 161 moves due to an operational input at theinstrument operating parts 131A and 131B, the second belt member 172 ispulled in one direction accompanying this, and the large diameter part175A begins to rotate. The second chain belt 173 that is housed insidethe grooves 157 b engages with the small diameter parts 175B. Thebending wires 117C and 117D which extend from the first sheath 203 areeach connected to an end of the second chain belt 173. Furthermore,three sets of grooves 157 b are prepared in the gear box 157 a. Bypairing these with the different diameter large diameter parts 175A, itis possible to select a reduction gear ratio at the horizontal bendingoperating part 157.

The rotation operating part 150 is disposed further toward the front endside than the first arm clamp 152A and the second arm clamp 152B of thefixed frame 145B, and is provided with a sheath connector 181, which hasa rotation knob and to which the base end of the first sheath 203 isconnected; and a rotation support 182 for supporting the sheathconnector 181 in a manner to enable rotation. Through-holes 183 aredisposed in the rotation support 182 through which the first arm member208A and the second arm member 208B, which are respectively connected tothe first arm clamp 152A and the second arm clamp 152B, the video cable220, and the like, are inserted.

As shown in the schematic cross-sectional view in FIG. 37, the sheathadvance/retract part 191, which is connected to the first arm clamp152A, is provided with a first tubular member 191 a, a second tubularmember 191 b which is disposed nested inside the first tubular member191 a, and a die part 191 c that supports the base end of the secondtubular member 191 b. An instrument sheath 192 is installed between thedie part 191 c on the base end side and the attachment part 158, thisinstrument sheath 192 connecting an opening of the die part 191 c and anopening of the tubular member 193 of the attachment part 158. Theinstrument insertion part 125 having a coil sheath that is connected togripping forceps or the like at the front end is inserted into thesheath advance/retract part 191 and the instrument sheath 192. Of thetwo tubular members 191 a and 191 b that are disposed in nesting form,the first tubular member 191 a is supported by the first arm clamp 152Aand is fixed in place to the fixed frame 145B, while the second tubularmember 191 b is connected to the die part 191 c and is fixed in place tothe moving frame 145A. Accordingly by advancing and retracting themoving frame 145A with respect to the fixed frame 145B, it is possibleto advance and retract the second tubular member 191 b with respect tothe first tubular member 191 a, and thereby advance and retract theinstrument insertion part 125 which is inserted inside the secondtubular member 191 b with respect to the first sheath 203. As a result,the high-frequency scalpel 205A that is disposed at the front end of thefirst arm member 208A can be made to project out from the front end ofthe front end part 215A, and to be retracted back from this projectingposition.

The open/close operating part 146 is attached to the frame member 170 ofthe fixed frame 145B. As shown in FIGS. 38 through 40, the open/closeoperating part 146 is provided with an open/close operating part mainbody 153; an open/close handle 155 to which the base end of the bendingopening/closing wire 244 is connected and which can advance and retractwith respect to the open/close operating part main body 153; and a gear154 for restricting the position of the open/close handle 155 withrespect to the open/close operating part main body 153. A rack 155 a isformed at the open/close handle 155 for restricting movement toward thefront end side when the open/close handle 155 is pulled toward thehand-held side. This rack 155 a is for restricting the advance of theopen/close handle 155 with respect to the open/close operating part mainbody 153 through engagement with a claw 154 b of a gear 154 that isprovided inside the open/close operating part main body 153. In thisrestricted state, the claw 154 b of the above-mentioned gear 154 can bemoved away and released from the rack 155 a by pressing a release button154 c that is provided opposite the claw 154 b via a gear main body 154a of the gear 154. When a starting state for the open/close mechanism210 is defined as the state in which the first arm member 208A and thesecond arm member 208B are closed at a position along the direction ofthe central axis C1 of the first sheath 203, then, in this startingstate, the open/close handle 155 is set so as to be positioned towardthe front end of the open/close operating part main body 153.

The sheath operating part 194 is disposed vertically positioned to astand part 194A that is attached to the gear box 157 a of the fixedframe 145B. The sheath operating part 194 can be freely attached to orreleased from the stand part 194A. The sheath operating part 194 isprovided with a bending knob 195 for bending operation of the bendingpart 203B provided at the front end side of the first sheath 203. Theoperating sheath 204 which extends from the first sheath 203 isconnected to a front end part 194 a of the sheath operating part 194.Four bending wires 201B, which are inserted into each of the jointwheels 201 of the bending part 203B are inserted into the operatingsheath 204. As in the case of the typical medical treatment endoscope,the four bending wires 201B can be advanced or retracted by turning thebending knob 195 that is provided at the sheath operating part 194,enabling bending operation of the bending part 203B to be carried out bythe aforementioned advance/retract operation.

Next, the operation of the embodiment of the present invention will beexplained.

When opening the first arm member 208A and the second arm member 208Bwith respect to the first sheath 203 from the starting state shown inFIGS. 26 and 27, the open/close handle 155 is slid with respect to theopen/close operating part main body 153 a predetermined distance towardthe hand-held side. At this time, the bending opening/closing wire 244is thus retracted with respect to the sheath front end part 203A towardthe hand-held side, and the open/close operating part 243 is retracted.Accompanying this, the linking part 236 receives a rotational torquedirected away from the central axis of the first sheath 203, and, as aresult, the other end 236 b of the linking part 236 is rotated by aspecific angle in the direction away from the central axis C1 of thefirst sheath 203, with the one end 236 a of the linking part 236 servingas the rotational center. As shown in FIGS. 23 through 25, the support237 rotates with respect to the first sheath 203, and the first armmember 208A and the second arm member 208B open. In this state, theposition of the open/close handle 155 is fixed in place by the rack 155a of the open/close operating part 146, and the position of the bendingopening/closing wire 244 is thus fixed in place with respect to thefirst sheath 203.

In contrast, when closing the first arm member 208A and the second armmember 208B with respect to the front end side of the first sheath 203,the open/close handle 155 is advanced forward with respect to theopen/close operating part main body 153, while pressing on the releasebutton 154 c. At this time, the bending opening/closing wire 244 isadvanced forward with respect to the front end side of the first sheath203. Accompanying this, the rotational torque applied on the linkingpart 236 is released, and the other end 236 b of the linking part 236 isrotated in a direction toward the central axis C1 of the first sheath203, employing the one end 236 a of the linking part 236 as therotational center. As a result, the support 237 rotates with respect tothe first sheath 203 and the first arm member 208A and the second armmember 208B close, i.e., resumes the starting state.

In the case where the high frequency scalpel 205A projecting out fromthe front end of the first arm member 208A is to be projected out stillfurther from the front end of the first arm member 208A, this isaccomplished by advancing the moving frame 145A of the operating part151 with respect to the fixed frame 145B. At this time, the entirety ofthe moving frame 145A moves in the direction that brings it closer tothe first arm clamp 152A, and the members positioned in hand-held sidefrom the second tubular member 191 b of the sheath advance/retract part191 which is supporting the instrument insertion part 125, move in adirection that brings it closer to the first tubular member 191 a, andthe instrument insertion part 125 is advanced inside the first sheath203. In this case, the first arm member 208A is fixed in place to thefirst arm clamp 152A, so that only the high frequency scalpel 205A isprojected further out from the front end part 215A of the first armmember 208A. Furthermore, since the bending wires 117A, 117B, 117C, and117D are separated from the instrument insertion part 125 at the firstarm clamp 152A, the bending state of the bending part 207 is not alteredby the operation to advance the moving frame 145A.

In contrast, when moving the high frequency scalpel 205A toward thehand-held side of the first arm member 208A, the moving frame 145A ofthe operating part 151 is retracted with respect to the fixed frame145B. At this time, the members positioned at the hand-held side fromthe second tubular member 191 b of the sheath advance/retract part 191which is supporting the instrument insertion part 125, are retractedwith respect to the first tubular member 191 a. In this way, the highfrequency scalpel 205A is again disposed at its starting state position.

When bending the first arm member 208A and the second arm member 208B inthe vertical direction, the vertical bending operating part 156 ismanipulated. In other words, the instrument operating parts 131A and131B which are attached to the attachment parts 158 are gripped andmoved in the vertical direction. In this case, the attachment part 158moves vertically with the limits of the second movement restrictingmember 161, while at the same time, the first movement restrictingmember 160 moves together with the attachment part 158 along the firstbending guides 196 in the vertical direction. Here, the first die parts160 b of the first movement restricting member 160 also move in thevertical direction, so that the first belt member 165 moves accompanyingthis, and the first gear 168 is rotated in either direction. At thistime, the first chain belt 167 is rotated in either direction, and,accompanying this, one of the bending wires 117A and 117B is advancedwith respect to the first sheath 203, while the other is retracted. Inthis way, the joint wheels 216 of the bending part 207 are inclinedaccompanying the movement of the bending wires 117A and 117B, and bendvertically.

In contrast, when bending the first arm member 208A and the second armmember 208B in the horizontal direction, the horizontal bendingoperating part 157 is manipulated. In other words, the instrumentoperating parts 131A and 131B which are attached to the attachment parts158 are gripped and moved in the horizontal direction. In this case, theattachment part 158 moves horizontally within the limits of the firstmovement restricting member 160, while at the same time, the secondmovement restricting member 161 moves together with the attachment part158 along the paired second bending guides 197 in the horizontaldirection. Here, the second die parts 161 b of the second movementrestricting member 161 also move in the horizontal direction, so thatthe second belt member 172 moves accompanying this, and the second gear175 is rotated in either direction. At this time, the second chain belt173 is rotated in either direction, and, accompanying this, one of thebending wires 117C and 117D is advanced with respect to the first sheath203, while the other is retracted. In this way, the joint wheels 216 ofthe bending part 207 are inclined accompanying the movement of thebending wires 117C and 117D, and bend horizontally.

When rotating the first sheath 203 with respect to the operating part51, the rotation knob provided to the sheath connector 181 of therotation operating part 150 is gripped and rotated in the desireddirection. As a result, the sheath connector 182 rotates relative to therotation support 181, causing the first sheath 203 to rotate in thedesired direction relative to operating part 151.

In this medical treatment endoscope 200, the first arm member 208A andthe second arm member 208B that are inserted into the first sheath 203can be moved away from the central axis C1 of the first sheath 203 usingthe open/close mechanism 210, and can be further bent at the bendingparts 207 of the first arm member 208A and the second arm member 208B.As a result, it is possible to visually confirm the distal ends of thefirst arm member 208A and the second arm member 208B when a sufficientvisual field has been secured for the image pick-up unit 211. As aresult, it is possible to reliably and safely carry out the medicalprocedure. In this case, the axial force generated by advancing orretracting the bending opening/closing wires 244 with respect to thefirst sheath 203 is converted into the opening/closing forces for thefirst arm member 208A and the second arm member 208B at the linking part236 of the open/close mechanism 210. This point is equivalent to that ofthe first embodiment. However, in this embodiment, the opening/closingoperation of the first arm member 208A and the second arm member 208B iscarried out smoothly with a smaller operating force, so that the armmembers can be opened even wider.

Namely, in the medical treatment endoscope 1 according to the firstembodiment, the bending opening/closing wire 35 is connected to theother end 36 b of the linking part 36, and the open/close mechanism 10is operated by advancing and retracting the bending opening/closing wire35. In this case, as shown in FIG. 8A, the bending opening/closing wire35 that is connected to the other end 36 b of the linking part 36 on thearm member 8B side has a flexed part 35 a that is flexed at a positionthat is advanced from the sheath front end part 3A. Furthermore, asshown in FIGS. 14 and 15, a flexed part 35 a is also provided on the armmember 8A side that flexes at the front end of the guide 41A that housesthe bending opening/closing wire 35. For this reason, when opening orclosing the arm members 8A and 8B, this flexed part 35 a creates slidingresistance, increasing the operating force for bending opening/closingwires 35.

Furthermore, as shown in FIG. 8, the bending opening/closing wire 35 issupported by the flexed part 35 a, and has the construction such thatthe front end side thereof moves along with the opening/closingoperation of the arm members 8A and 8B. It is therefore difficult toopen the first arm member 8A and the second arm member 8B to an anglegreater than 45° with respect to the central axis C1 of the first sheath3.

Accordingly, in the medical treatment endoscope 200 according to thisembodiment, the construction is employed in which the one end 236 a ofthe linking part 236 is connected to the open/close operating part 243at a position that is further to the front end side of the first armmember 208A and the second arm member 208B than the support part 237,and the pantograph structure that is formed by the two linking parts 236and the two support parts 237 is altered according to the advance orretraction of the open/close operating part 243. As a result, although arelatively larger operational force is required when initiating theopening operation, the amount of operating force required decreases asthe linking part 236 and the support 237 are opened. Therefore,operation of the arm member near the lesion site can be carried outsmoothly. Furthermore, since the open/close operating part 243 movestogether with the slide member 242 that is disposed at the first sheath203 side, along the direction of advance and retraction of the bendingopening/closing wire 244, there is no change in the direction ofoperation accompanying the opening/closing operation as in the case ofthe bending opening/closing wire 35 according to the first embodiment,and the amount of movement of the bending opening/closing wire 242 iscommunicated without change to the linking part 236. As a result, a moreefficient opening/closing movement can be carried out. In thisembodiment, opening and closing are carried out by communication of theinput on the hand-held side to the pantograph of the open/closemechanism 210 via the bending opening/closing wire 244. However, it is acharacteristic of wire driving that the force from pushing the wire isless than the force from pulling the wire. For this reason, the presentembodiment is constructed so that operation can be carried out bypulling the bending opening/closing wire 244 when opening the armmembers 208A and 208B from a closed state, which requires a relativelylarge force. Conversely, the present embodiment is constructed so as toemploy an arrangement in which the power factor of the pantograph isbeneficial when closing arm members that are open, so that only a smallforce need be communicated from the bending opening/closing wire 244.

Moreover, the more that the bending opening/closing wire 244 isretracted, the further apart the first arm member 208A and the secondarm member 208B are spread, such that the first arm member 208A and thesecond arm member 208B can be spread apart without limit within theparameters of allowable movement of the pantograph. For this reason, thefirst arm member 208A and the second arm member 208B can be widelyspread apart to a position in which the angle exceeds 45° with respectto the central axis C1. As a result, it is possible to prevent the fieldof view from becoming narrower due to entrance of the first arm member208A and the second arm member 208B into the field of view of the imagepick-up unit 211. In this embodiment, the opening/closing angle of thefirst arm member 208A and the second arm member 208B is adjustedaccording to the length of the linking part 236 and the support 237 sothat the front end part of the arm member 208A and the front end part ofthe second arm member 208B form an angle of 50° or greater at theinstrument which is 50 to 70 mm distal from the objective lens 223 ofthe image pick-up unit 211. The angle of opening of the first arm member208A and the second arm member 208B can be easily adjusted by suitablychanging the length of the linking part 236, thereby offering superiorfreedom of construction.

Furthermore, in this embodiment, openings 203 a are provided at thesheath front end part 203A, enabling the bending parts 207 to beadvanced outward via these openings 203 a. By providing this type ofconstruction, the first arm member 208A and the second arm member 208Bcan open beyond the objective lens 223 at the base end side of the firstsheath 203. As a result, the arm members 208A and 208B are less apt toenter into the field of view of the image pick-up unit 211, making iteven easier to see the instrument.

In addition, the open/close operating part 243 and the linking part 236are disposed to the first arm member 208A and the second arm member 208Bon the side of the arm members that is opposite the image pick-up unit211. As a result, it is possible to prevent the open/close operatingpart 243 from entering into the field of view of the image pick-up unit211. Furthermore, since the open/close operating part 243 is pulledtoward the hand-held side when opening the first arm member 208A and thesecond arm member 208B, on this point as well, the construction limitsinterference with the field of view. In addition, the slide member 242,which restricts the open/close operating part 243 so that it moves onlyin the direction of the central axis C1 of the first sheath 203, isdisposed at the clearance that is formed at the center of the firstsheath 203 as a result of disposing the first arm member 208A and thesecond arm member 208B, which are roughly round in cross-section,adjacent to one another. Accordingly, the construction provides anopen/close mechanism 210, while at the same time conserving space insidethe first sheath 203.

Furthermore, in the preceding first embodiment, the more that the firstarm member 8A and the second arm member 8B are opened, the smaller theangle becomes at flexed part 35 a of the bending opening/closing wire 35and the greater the force required for operation becomes. Moreover, alarge force is also required to hold the arms in the open state. Inparticular, when a force is continuously applied to hold the arms in theopen state, there is a chance that the member near the flexed part 35 aor the linking part 36 could break. In contrast, in this embodiment, theforce required for operation when the first arm member 208A and thesecond arm member 208B are in the open state is small, and the force forholding the arms in the open state is little. Furthermore, when aplate-shaped member is employed for the linking part 236, the rigidityis increased. For this reason, it is possible to avoid the applicationof a force on the open/close mechanism 210 when the first arm member208A and the second arm member 208B are in the open state, so thatdamage to the linking part 236, etc. is unlikely to occur, andreliability can be improved.

In this embodiment, the bending opening/closing wire 244 is pulledtoward the hand-held side when opening the first arm member 208A and thesecond arm member 208B. Thus, it is possible to adjust the force that iscommunicated to the bending parts 207, so that the opening angle of thefirst sheath 203 with respect to the central axis C1 can be finelyadjusted. Furthermore, by pulling the open/close handle 155 at once withrespect to the open/close operating part main body 153 toward thehand-held side until it comes into contact with a contact point, so thatthe opening angle between the first arm member 208A and the second armmember 208B with respect to the central axis C1 is set suitable, it ispossible to obtain a simplified open/close operation of the first armmember 208A and the second arm member 208B.

Furthermore, the first embodiment had the construction that did notpermit changing the rotation or inclination of the front end part.Moreover, by using the medical treatment endoscope according to thefirst embodiment, there are unreachable points for the instrument sincethe bending radius of the first sheath 3 is large, resulting from a tubemade of a styrene-derived elastomer being employed as the first sheath3. In this embodiment, a bending part 203B is provided at the front endside of the first sheath 203 that connects the multiple joint wheels201. By providing the bending part 203B, the bending radius at the frontend part becomes smaller, and it is possible to freely direct the sheathfront end part 203A in an optional direction. As a result, the approachof the instrument is facilitated and the procedure can be carried outsmoothly.

Furthermore, the first arm member 208A and the second arm member 208Bare constructed so as not to advance or retract with respect to thesheath front end part 203A due to the supports 237. Therefore, only thehigh frequency scalpel 205A or other such instrument projecting out fromthe front end part 215A of the first arm member 208A advances orretracts with respect to the first arm member 208A. In the firstembodiment, the state in which the instrument is directed along thecentral axis of the first sheath 203 is designated as the startingstate, regardless of the open/close status of the first arm member 8Aand second arm member 8B. Furthermore, based on the idea of being ableto move the instrument forward/backward, up/down or left/right from thestarting state, the construction was provided to enable the first armmember 8A, which is provided with a bending part 7, to advance andretract with respect to the first sheath 3. However, defining the statein which the first arm member 208A and the second arm member 208B areopened by the open/close mechanism 210, and the instrument at the frontend is directed inward so that the front end and the affected part comeinto the field of view of the image pick-up unit 211, to be the startingstate of the first arm member 208A and the second arm member 208B isnatural. In this starting state, the construction is employed in whichonly the instrument projecting out from the front end part 215A, and notthe first arm member 208A, is advanced and retracted, so as to enableadvance and retract of the instrument with respect to the affected part.

Next, the bending operation of the first arm member 208A and the secondarm member 208B via operation of the instrument operating parts 131A and131B can be carried out with an even smaller amount of force at theoperating part 151 of the medical treatment endoscope 200 according tothis embodiment.

In the preceding first embodiment, the attachment part 58 is supportedin a manner to enable relatively free movement within the frames of therectangular, plate-shaped first movement restricting member 60 and thesecond movement restricting member 61. The construction is provided inwhich the operational input to the forceps operating part 31 that isattached to the attachment part 58 is communicated via the firstmovement restricting member 60 and the second movement restrictingmember 61 to the first belt member 65, which is connected to the endpart of the first movement restricting member 60, and the second beltmember 72, which is connected to the end part of the second movementrestricting member 61. In this construction, in the case of anoperational input to grip the forceps operating part main body 32 andmove it vertically or horizontally, when the forceps operating part mainbody 32 is inclined in the direction of input of the operation, with theattachment part 58 employed as a fulcrum, then the attachment part 58 ispressed against the first movement restricting member 60 and the secondmovement restricting member 61, leading to resistance. As a result,there is an undesirable increase in the force required for operation.

In addition, the first belt member 65 and the second belt member 72 areconnected to the one end 60 a of the first movement restricting member60 and the one end 61 a of the second movement restricting member 61,respectively. For this reason, the force for moving the first beltmember 65 and the second belt member 72 becomes focused at the end partof the first movement restricting member 60 and the second movementrestricting member 61. A movement is generated as a result, leading toresistance in the movement. As a result, there is an undesirableincrease in the force required for operation.

Accordingly, in this embodiment, the construction is provided in whichthe first movement restricting member 160 and the second movementrestricting member 161 are composed of the slide rails 160 a and 161 a,respectively, and the slide blocks 158A and 158B of the attachment part158 engage with these respective slide rails 160 a and 161 a to permitsliding. According to this construction, when there is an operationalinput to the instrument operating parts 131A and 131B, the attachmentpart 158 can be smoothly displaced with a light amount of operatingforce, without inclining resulting from the employment of the attachmentpart 158 as a fulcrum. Furthermore, the first belt member 165 isconnected to the first die parts 160 b that are provided at thelongitudinal center of the slide rails 160 a. The first movementrestricting member 160 is disposed on the frame member 170 via the firstbending guide 196, which has the slide rail 196 a and the slide block196 b that engages with the slide rail 196 a in a manner to enablesliding. According to this construction, it is possible to reducegeneration of a movement during the communication of the operationalinput from the first movement restricting member 160 to the first beltmember 165 regardless of the position of the attachment part 158 on thefirst movement restricting member 160. This also applies to theconnection between the second movement restricting member 161 and thesecond belt member 172. As a result, it becomes possible to realize aneven greater reduction in the amount of operating force required.

Furthermore, by sliding the moving frame 45A with respect to the fixedframe 45B via the slide mechanisms 148 and 190, the instrument insertionpart 125, which is inserted into the first arm member 208A, is made toadvance and retract with respect to the first arm member 208A and thefirst sheath 203. As a result, the high frequency scalpel 205A or othersuch instrument can be made to project out or retract back from thefront end part 215A of the first arm member 208A. Accordingly, it ispossible to increase the procedure limits for the instrument for thefirst arm member 208A and the first sheath 203. Furthermore, theconstruction is provided in which the advance and retraction of theinstrument is carried out by varying the length of the instrumentinsertion part 125 with respect to the first arm member 208A, enablingthe advance and retraction of the instrument to be carried out smoothly.This type of construction provides the benefit of enabling theadvance/retract mechanism for the instrument to be provided at anoptional position. Furthermore, in the operating part 151 in thisembodiment, the sheath advance/retract part 191 is provided at theperpendicular part that extends from the first sheath 203 to the bendingoperating part 147, which is essential basically. As a result, thisconstruction succeeds in shortening the overall length of the operatingpart 151 while at the same time providing an instrument advance/retractmechanism. Moreover, since the sheath advance/retract part 191 isprovided farther toward the first sheath 203 side than the part bendingthe instrument insertion part 125, the resistance between the instrumentsheath 192 and the instrument insertion part 125 which is generated atthe bent part of the instrument insertion part 125 is not receivedduring operations to advance and retract the instrument. As a result,the operation of advancing and retracting the instrument can beaccomplished with a light force.

Moreover, the first tubular member 191 a and the second tubular member191 b that are disposed in a nesting manner are relatively long, so thatit is possible to greatly adjust the length of the instrument insertionpart 125. As a result, in addition to being able to increase theadvance/retract width of the instrument, the sheath advance/retract part191 can also be used to absorb differences in the length of theinstrument insertion part 125 when exchanging instruments.

Furthermore, the sheath operating part 194 which is provided with abending knob 195 for operating the bending part 203B can be freelyattached to and released from the stand part 194A that is attached tothe gear box 157 a of the fixed frame 145B. According to thisconstruction, when inserting the inserted part of the medical treatmentendoscope 200 into a body cavity, the sheath operating part 194 can beoperated after being detached from the stand part 194A, therebyimproving operability during insertion. The sheath operating part 194 isconstructed to attach to the stand part 194A when performing atreatment, to enable fine adjustment of the bending angle of the bendingpart 203B by rotational operation of the bending knob 195.

In this embodiment as well, the open/close mechanism 210 can be operatedby operating the open/close operating part 146 of the operating part 151to advance and retract the bending opening/closing wires 244 withrespect to the first sheath 203. Furthermore, by performing operationsin the state of the instrument operating part 131B of the grippingforceps 205B attached to the bending operating part 147, not only canopen/close operation of the paired forceps pieces 226A and 226B of thegripping forceps 205B be performed, but it is also possible to carry outbending operation of the bending part 207. Thus, the procedure isfacilitated. Moreover, by rotating the instrument operating part 131with respect to the attachment part 158, the instrument can be rotatedto the desired state. Moreover, since the bending part 207 is employedonly for bending an instrument such as gripping forceps 205B, greaterbending is possible, and a larger force can be output, as compared toconventional endoscopes in which there is a structure that is requiredto bend a plurality of apparatuses such as instruments, video cable (theimage guide in an optical endoscope), light guides and the like.

Fourth Embodiment

A fourth embodiment will now be explained with reference to the figures.The medical treatment endoscope according to the present embodimentrepresents a further improvement over the medical treatment endoscopeaccording to the first embodiment.

As illustrated in FIG. 43, a medical treatment endoscope 300 includes afirst sheath 301 similarly configured to the medical treatment endoscope1 according to the first embodiment; a second sheath 303A having a firstarm member 302A and protruding from the first sheath 301; and a thirdsheath 303B having a second arm member 302B and protruding from thefirst sheath 301. Since the first arm member 302A and the second armmember 302B have approximately the same configuration, the first armmember 302A will be mainly explained hereafter.

As illustrated in FIGS. 44 to 52, the first arm member 302A includes: afirst bending part 306 having a first joint ring 305 pivotally attachedthereto; and a second bending part 308 where the first joint ring 305bends in a first bending direction and in a second bending directioncrossing with the first bending direction around the center of a firstdirection D1 that is parallel with a longitudinal direction (centralaxis direction) C of the first sheath 301, a second joint ring 307 whichbends in the second direction D2 away from the longitudinal direction ofthe first sheath 301 is pivotally attached to the second base endbending part 308A, the base end of the second base end bending part 308Ais joined to the sheath front end part 301A of the first sheath 301, thesecond joint ring 307 bending in the first direction D1 from the seconddirection D2 is pivotally attached to the second bending part 308, andthe tip of the second tip end bending part 308B is joined to the baseend of the first bending part 306.

As illustrated in FIGS. 53 to 60, the first joint ring 305 is pivotallysupported at four points by support axis parts 310 which are disposed ona plane defined by a vertical direction of an image observed with aviewing device 12 (up and down direction in FIG. 56) and by a horizontaldirection (right and left direction in FIG. 56) so that the vertical andhorizontal direction are orthogonal (AX1 direction and AX2 direction inFIG. 56) and 45 degrees offset.

The second joint ring 307 and a second joint ring 307′ are pivotallysupported by four support axis parts 310 that are disposed on a planedefined by two directional lines (AX3 and AX4 illustrated in FIG. 56)rotatively offset by a predetermined angle with respect to thedirections AX1 and AX2. The second bending part 308 therefore bends inthe direction which passes through an object lens (objective opticalsystem) 23 provided at the viewing device 12 and inclines relative to aplane orthogonal to the longitudinal direction C of the first sheath301, and the tip of the second bending part 308 separates away from theperspective field of the viewing device 12.

The second joint rings 307 and 307′ are pivotally attached to each otherand urged in a direction so that a linear state of the second bendingpart 308 is maintained. A tip end surface 307 a and a base end surface307 b are formed on the second joint rings 307 and 307′ so that the tipend surface 307 a and the base end surface 307 b make contact with eachother with the maximum bent state of the second bending part 308, and sothat the tip end surface 307 a and the base end surface 307 b incline bya predetermined angle so as to be able to separate from each otheraccording to deformation of the second bending part 308 into linearstate.

A tip part 15 and the first bending part 306 are pivotally attached toeach other via a solid short pipe 311A. The first bending part 306 andthe second bending part 308 are pivotally attached to each other via asolid short pipe 311B. The second bending part 308 and the sheath frontend part 301A are pivotally attached to each other via a solid shortpipe 311 C. The second base end bending part 308A and the second tip endbending part 308B are pivotally attached to each other via a solid shortpipe 311D.

Notches 312 extending in the longitudinal directions of the firstbending part 306 and second bending part 308 are provided to the secondjoint rings 307 and 307′ and the short pipes 311B, 311C, 311D. Providedon the short pipe 311B are the notches 312′ at four points in theup-down direction and right-left direction. Provided on the short pipe311D is a notch 312′ having an enlarged open end so that two neighboringcoil tubes can be inserted. Provided on the short pipe 311C is a similarnotch 312′ at the position 180 degrees rotated from there.

Fitted to the notch 312 of the short pipe 311B are the tips of coiltubes 313A, 313B, 313C, 313D. The tip of the coil tube 313E is fitted tothe notches 312 and 312′ of the short pipe 311D, and the coil tubes313A, 313B, 313C, 313D are inserted therethrough. The tip of the coiltube 313F is fitted to the notches 312 and 312′ of the short pipe 311C,and the coil tubes 313A, 313B, 313C, 313D, and 313E are insertedtherethrough.

In addition, the medical treatment endoscope 300 includes first bendingwires (first operating members) 315A, 315B, 315C, and 315D, insertedthrough the first bending part 306 and the second bending part 308, forbending the first bending part 306; and second bending wires (secondoperating members) 316A and 316B, inserted through the second bendingpart 308, for bending the second bending part 308.

The tips of the first bending wires 315A, 315B, 315C, 315D are connectedto the short pipe 311A. The first bending wires 315A, 315B, 315C, 315Dare retractably inserted through the coil tubes 313A, 313B, 313C, 313Drespectively between the short pipe 311B and a manipulation side of theoperation part which is not shown in the drawings. That is, they areinserted in the up-down direction and in the right-left direction ofFIG. 56.

The first bending wires 315A, 315C in this state are connected to avertical bending operating part of the operation part which is not shownin the drawings. The first bending wires 315B, 315D are connected to ahorizontal bending operating part of the operation part which is notshown in the drawings. Operating these operation parts extends andretracts the first bending wires 315A, 315B, 315C, 315D respectively;thereby bending the first bending part 306 in the desirable direction.

The tip of the second bending wire 316A is connected to the short pipe311D and retractably inserted through the coil tube 313E between theshort pipe 311C and the operation part for manipulation. The tip of thecoil tube 313E is connected to the short pipe 311C. That is, the coiltube 313E is inserted at a clockwise offset position by 45 degreesrelative to the direction AX3 as illustrated in FIG. 56. The base end ofthe second bending wire 316A is connected to an open/close operatingpart which is not shown in the drawings. Operating the open/closeoperating part extends and retracts the second bending wire 316A;thereby bending the second base end bending part 308A.

The tip of the second bending wire 316B is connected to the short pipe311B and retractably inserted through the coil tube 313F between theshort pipe 311D and the operation part for manipulation. The tip of thecoil tube 313F is connected to the short pipe 311D. That is, the coiltube 313F is inserted at a counter clockwise offset position byapproximately 45 degrees relative to the direction AX4 as illustrated inFIG. 56. The base end of the second bending wire 316B is connected tothe open/close operating part which is not shown in the drawings.Operating the open/close operating part extends and retracts the secondbending wire 316B; thereby bending the second tip end bending part 308B.

The diameter of first bending wires 315A, 315B, 315C, 315D and thesecond bending wires 316A, 316B is 0.45 mm, which is greater than thatof 0.36 mm for bending wires 17A, 17B, 17C, and 17D in the medicaltreatment endoscope 1 according to the first embodiment. Applied on thesurfaces of the first bending wires 315A, 315B, 315C, 315D and thesecond bending wires 316A, 316B are a PTFE (polytetrafluoroethylene)coating for reducing friction resistance.

As shown in FIG. 61, provided through the first sheath 301 and sheathfront end part 301A is a channel 318 that allows an endoscopic treatmentinstruments, e.g., a grasping forceps 5A to be freely insertedtherethrough.

In addition, as illustrated in FIGS. 62 to 64, the medical treatmentendoscope 320 may further include a flexible storage sheath 321 forcontaining the tip portions of the first arm member 302A and second armmember 302B in an extended condition. Provided in the storage sheath 321are a first arm member lumen 322A which allows the first arm member 302Ato be inserted therethrough; a second arm lumen 322B which allows thesecond arm member 302B to be inserted therethrough; andextension/retraction operating wires 323A and 323B for bending thesecond bending part 308 while protruding and retracting the arm members302A and 302B from each lumen 322A, 322B. The tip of theextension/retraction operating wire 323A connected to the short pipe311B is inserted through the first arm member lumen 322A or the secondarm lumen 322B, and is connected to the base end of the first arm memberlumen 322A or the second arm lumen 322B.

The tip of the extension/retraction operating wire 323B connected to theshort pipe 311D is inserted through the first arm member lumen 322A orthe second arm lumen 322B, and is connected to the base end of the firstarm member lumen 322A or the second arm lumen 322B.

A drawing force is applied to the extension/retraction operating wires323A and 323B according to the protrusion of the first arm member 302Aand second arm member 302B from the tip of the storage sheath 321 causedby the movement of the storage sheath 321 toward the operating part 325.This results in bending the second bending part 308 into a desirabledirection since the extension/retraction operating wires 323A and 323Bact similarly to the second bending wires 316A, 316B.

Next, the operation of the medical treatment endoscope 300 according tothe present embodiment will be explained.

As illustrated in FIG. 65, a bending part 7 of the medical treatmentendoscope according to the first embodiment must swing in a range ofangle θ for conducting a predetermined treatment by opening the firstarm member 8A and the second arm member 8B relative to the first sheath301. Some axial force caused by the extending and retracting bendingwire is therefore used for bending the bending part 7. Therefore, asufficient force may not be generated sometimes at the tip of thetreatment instruments while maintaining the bending state of the bendingpart 7 if the first arm member 8A and the second arm member 8B are in abending state.

In contrast, as illustrated in FIG. 66, the second base end bending part308A of the medical treatment endoscope 300 according to the presentembodiment bends in the second direction D2 which separates away fromthe longitudinal direction C of the first sheath 301 and bends thesecond tip end bending part 308B in the first direction D1. This allowsthe first bending part 306 in the vicinity of the tip of the short pipe311B to bend in a range of angle θ that is the same as that of the firstembodiment by a stepwise swing by approximately ½θ around the firstdirection D1. Therefore a smaller axial force generated in the firstbending wires 315A, 315B, 315C, 315D can bend the bending part 7,thereby allowing the tip of the treatment instruments to generate agreater force.

Retracting the second bending wires 316A, 316B fixes the bending stateof the second bending wires 316A, 316B at the second bending part 308because a tip end surface 307 a of the second joint ring 307 in thesecond bending part 308 makes contact with a base end surface 307 b ofthe neighboring second joint ring 307 disposed separately. Thecontinuous retraction of the second bending wires 316A, 316B therebydesirably maintains the bending state of the second bending part 308.

Instead, slacking the second bending wires 316A, 316B releases thebending state of the second bending part 308. The restoration(resilience) in this state of the second bending part 308 into thelinear state increases while bending the second bending part 308 fromthe linear extending state. Therefore, slacking, i.e., stopping theretraction of the second bending wires 316A, 316B, releases the bendingstate of the second bending part 308.

A natural orifice medical procedure using the medical treatmentendoscope 300 according to the present embodiment will be explained withreference to a case as shown in FIGS. 67 and 68 where a gallbladderextraction is conducted similarly to the first embodiment by insertingthe medical treatment endoscope from the mouth M of the patient PT intothe stomach ST, forming an opening on the stomach wall, and inserting afirst sheath 301 of the medical treatment endoscope into the abdominalcavity AC.

The medical procedure according to the present embodiment includes: astep of inserting a medical treatment endoscope 300 in the vicinity ofan affected part; a step including disposing a high frequency knife(first endoscopic treatment instrument) 85 via the first arm member302A, disposing a grasping forceps (second endoscopic treatmentinstrument) 5 in the vicinity of the affected part via the second armmember 302B, and disposing a grasping forceps (third endoscopictreatment instrument) 5A in the vicinity of the affected part via achannel 318 of the first sheath 301; a step of bending the first armmember 302A and the second arm member 302B into different directionsrespectively; and a step of conducting treatment to the affected partwith the grasping forceps 5, the high frequency knife 85, and thegrasping forceps 5A.

In the insertion step, an overtube 90 is introduced into an abdominalcavity AC via an opening SO formed on a stomach ST similarly to thefirst embodiment.

Consequently inserted through a lumen 88 of the overtube 90 are a firstsheath 301, a second sheath 303A, and a third sheath 303B. The first armmember 302A and the second arm member 302B are protruded from the tip ofthe overtube 90.

The high frequency knife 85 is inserted into the second sheath 303A andthe first arm member 302A similarly to the first embodiment, and thegrasping forceps 5 is inserted into the third sheath 303B and the secondarm member 302B similarly to the case of the high frequency knife 85. Inaddition, the grasping forceps 5A is inserted into a channel 318provided in the first sheath 301.

The medical procedure transfers to the next step, i.e., the disposingstep. The second arm member 302B is positioned to grasp the affectedpart with the grasping forceps 5.

Operating an open/close operating part retracts a second bending wire316A until a tip end surface 307 a of a second joint ring 307 makescontact with a base end surface 307 b, thereby bending the second baseend bending part 308A from a longitudinal direction C to a seconddirection D2. Retracting further the second bending wire 316B until thetip end surface 307 a of the second joint ring 307 makes contact withthe base end surface 307 b bends a second tip end bending part 308B froma second direction D2 to a first direction D1. The direction of thesecond bending part 308 is thus fixed. Note that the second bendingwires 316A, 316B may be retracted simultaneously.

The bending operating part is consequently operated to swing the firstbending part 306 around the first direction D1 in order to inspect theaffected part with the viewing device 12. Operating a forceps-operatingpart which is not shown in the drawings extends, for example, thegrasping forceps 5 toward the second arm member 302B, thereby graspingand retracting a cervical part Ga of the gallbladder to expose a Calottrigone Ca.

The medical procedure in this state transfers to the treatment step.

A serosal membrane Se1 is incised a little at a time with the highfrequency knife 85 inserted in the first arm member 302A by operatingthe bending operating part. Conducted so as to apply adequate tension tothe incised part are picking the incised part with the grasping forceps5A inserted through the channel 318 while grasping the cervical part Gaof the gallbladder with the grasping forceps 5; grasping a serosalmembrane Se2 opposite the cervical part Ga of the gallbladder; drawingthe grasped serosal membrane Se2 toward the endoscopist; bending thefirst bending part 306 of the second arm member 302B away from thegrasping forceps 5A; and adjusting the drawing direction. Meanwhile,adipose tissue and fiber tissue including serous membrane are peeledwith the high frequency knife 85 while bending the first bending part306 of the first arm member 302A.

The gallbladder extraction is conducted by the operation similar to thefirst embodiment after identifying the gallbladder in this manner.

In addition to the previously explained gallbladder extraction, themedical treatment endoscope according to the present invention can beused for various manipulations, e.g., appendectomy, gastroduodenalbypass, liver biopsy, biopsy of the pancreas, tubal interruption, andhysterectomy.

In the medical treatment endoscope 300, provided instead of the solidopen/close mechanism provided at the medical treatment endoscopeaccording to the first embodiment are flexible second bending parts 308disposed at root parts of the first arm member 302A and the second armmember 302B. The length of the solid portions in the first arm member302A and the second arm member 302B shorter than that of the medicaltreatment endoscope provides higher flexibility, thereby improvinginsertability. The tip end surface 307 a and the base end surface 307 bformed in the second joint ring 307 incline so that the tip end surface307 a and the base end surface 307 b make contact with each other in thesecond joint ring 307 at the second bending part 308 when the secondbending wires 316A, 316B are drawn. Drawing the wires continuously tomaintain the contact between the tip end surface 307 a and the base endsurface 307 b allows the second bending part 308 to be fixed in thepredetermined bending state.

The first bending part 306 in this state can be bent with respect to thefirst direction D1. The bending range of the first bending part 306while using treatment instruments can be narrower than in the case ofthe medical treatment endoscope according to the first embodiment. Inaddition, it is possible to reduce a force necessary to bend the firstbending part 306 and increase an operation force at the tip of the firstarm member 302A and the tip of the second arm member 302B.

Also, since the first bending wires 315A, 315B, 315C, 315D are insertedat positions conforming in the vertical and horizontal directionsdefined on an image observed with the viewing device, intuitiveoperation while observing the image can be conducted. In addition, thesecond bending wires 316A, 316B inserted at the positions rotated by apredetermined degree relative to the positions of the first bendingwires 315A, 315B, 315C, 315D allow the second base end bending part 308Ato be directed outward and downward relative to the center of the firstsheath 301 when the second bending part 308 is bent. The affected part,the first arm member 302A, or the second arm member 302B that iscaptured by the viewing device 12 can be viewed or treated from abovesince the central axis of the first bending part 306 is beneath thecentral axis of the first sheath 301.

In addition, formed at the first joint ring 305 and the second jointring 307 are notches 312, 312′ extending in the longitudinal directionsof the first bending part 306 and the second bending part 308. The coiltubes 313A, 313B, 313C, 313D, 313E, and 313F are inserted through thenotches 312 and 312′. The outer diameters of the first joint ring 305and the second joint ring 307 may be desirably maintained if thethickness of the wall of these joint rings is increased.

The dispositions of the second bending wires 316A, 316B inserted throughthe second joint ring 307 are offset rotated by approximately 45 degreesrelative to the pivotally attached second joint ring 307. Therefore,retracting the second bending wire 316A to bend the second base endbending part 308A, or retracting the second bending wire 316B to bendthe second tip end bending part 308B rotates the neighboring secondjoint rings 307 or the joint rings 307′ around the axes AX3 and Ax4,thereby abutting the neighboring second joint rings 307 or 307′. Thesecond bending part 308 can be restored to a linear state by releasingthe bending state of the second bending part 308 retracted by the secondbending wires 316A, 316B since the pivotally attached second joint rings307 and 307′ are urged in a direction in which the linear state of thesecond bending part 308 is maintained. Therefore, a smaller outerdiameter of the bending part can be maintained.

The outer diameter of each bending wire greater than the diameter of thebending wire in the medical treatment endoscope can increase thewire-breaking force, thereby allowing retraction with a greater force.The PTFE coating applied on the wire surface can reduce the frictionresistance, thereby providing greater force at the tips of the wires.

Also, the channel 318 provided at the sheath front end part 301A of thefirst sheath 301 allows treatment instruments to be disposed in thechannel 318, thereby allowing more complex procedures to be conducted.Furthermore, the number of exchanges of the treatment instruments can bereduced.

A drawing force can be applied to the extension/retraction operatingwires 323A and 323B according to the protrusion of the first arm member302A and second arm member 302B from the tip of the storage sheath 321in use. The second bending part 308 can therefore be bent in a desireddirection simply by protruding the first arm member 302A and the secondarm member 302B from the tip of the storage sheath 321 since theextension/retraction operating wires 323A and 323B have similarfunctions as those of the second bending wires 316A, 316B.

Note that the second sheath 303A having the grasping forceps 5therethrough may be used as illustrated in FIG. 69.

In addition, the high frequency knife 85 is inserted into the channel318 provided in the first sheath 301 in this case.

The serosal membrane Se1 of the gallbladder is incised a little at atime with the high frequency knife 85 inserted through the channel 318in the treatment step conducted during the medical procedure explainedabove. As illustrated in FIGS. 70 and 71, conducted in order to apply anappropriate tension to the incised part are grasping the cervical partGa of the gallbladder with the grasping forceps 5 disposed at the secondarm member 302B; picking up the incised part with the grasping forceps 5disposed to the first arm member 302A; and grasping the serosal membraneSe2 opposite the cervical part Ga of the gallbladder. The first bendingparts 306 of the first arm member 302A and the second arm member 302Bare bent away in separate directions to adjust the retraction direction.Meanwhile, adipose tissue and fiber tissue including serous membrane canbe peeled by extending and retracting the high frequency knife 85inserted through the channel 318. Note that, in addition to the aboveexplanation, the first arm member 302A, the second arm member 302B, andthe channel 318 are variously combined regardless of the aboveexplanation.

Also, a medical treatment endoscope 332 may include a viewing unit 331having an illuminating lens 21 a and an object lens 23 that isextendable away from a sheath front end part 330A toward the tips of thefirst arm member 302A and the second arm member 302B as illustrated inFIG. 71.

In this case, a flexible protection tube 333 is configured to extendfrom the viewing unit 331 for containing and protecting an observationoptical system including the object lens 23 and the illuminating opticalsystem for introducing a light beam into the object lens 21 a. Note thatthese optical systems are not shown in the drawings. The protection tube333 is configured to be extendable relative to the storage lumen 335disposed in the first sheath 330.

The inserted state of the medical treatment endoscope 332 provides awide perspective since the viewing unit 331 is extendable to thevicinity of the tips of the first arm member 302A and the second armmember 302B when the first arm member 302A and the second arm member302B are inserted.

Fifth Embodiment

A medical treatment endoscope according to the present embodiment isfunctionally divided into an operation section for conducting necessarytreatments by means of arm sections and procedure instruments; and anendoscope operation section for operating an endoscope. The presentembodiment features in that the operation sections are operable inseparate locations from the endoscope. An operation section built in anendoscope operation section necessitates an operator to conduct all theoperations alone, i.e., inevitably complex operations. The presentembodiment enables two operators to share operations, i.e., operating anendoscope and conducting a treatment; thus, facilitating the operations.

As illustrated in FIG. 72, an endoscope insertion section 503 fullyintegrated with a medical treatment endoscope 501 extends from an end ofan endoscope insertion section 502. The configuration of the elongatedand flexible endoscope insertion section 503 is the same as that of theprevious embodiments. That is, the endoscope insertion section 503 has afirst sheath 301 having a first arm section 302A and a second armsection 302B on the tip of the first sheath 301. Treatment sections 505Aand 505B of procedure instruments 504A and 504B each protrude from thetips of the arm sections 302A and 302B. A first bending part 306 and asecond bending part 308, in this order from the tips of the tips of thearm sections 302A and 302B, are formed to each arm section 302A and302B. Combined use with a third bending section 203B formed to the firstsheath 301 enables bending operation in a human body. The first armmember 302A and second arm member 302B may be passed through a secondsheath 303A and a third sheath 303B respectively. Meanwhile, theoperation section 520 is enlarged in FIG. 72 to help betterunderstanding.

A forceps cap 510 is provided to a side of the endoscope insertionsection 502 near an end that continues to the endoscope insertionsection 503. The forceps cap 510 communicates to an operation channelformed in the first sheath 301. Inserting another procedure instrument,which is not shown in the drawing, from here enables the procedureinstrument to protrude from the tip of the endoscope insertion section503. In addition, disposed to the endoscope insertion section 502 are aswitch 511, an angle knob 512, and a universal cable 513 that isconnected to a control apparatus that is not shown in the drawing. Forexample, operating the switch 511 provides air-supply, water-supply, andsuction through a channel formed in the first sheath 301. Operating theangle knob 512 bends the third bending section 203B into four directionswith respect to an axial line.

In addition, an elongated flexible connection sheath 515 extends fromthe other end of the endoscope insertion section 502. An operationsection 520 is disposed at an end of the connection sheath 515.

The operation section 520 has a base 521 that fixes the connectionsheath 515. Attached to the base 521 are a first operation unit 530A anda second operation unit 530B. The first operation unit 530A has anoperation stick 531A into which an operation section 506A of theprocedure instrument 504A is inserted. The procedure instrument 504A ispassed through the first arm member 302A. The operation section 506A issupported by the operation stick 531A so as to be capable of extendingand retracting in the axial line and bending in four directions withrespect to the axial line. The second operation unit 530B has anoperation stick 531B into which an operation section 506B of theprocedure instrument 504B is inserted. The procedure instrument 504B ispassed through the second arm member 302B. The operation section 506B issupported by the operation stick 531B so as to be capable of extendingand retracting in the axial line and bending in four directions withrespect to the axial line. Furthermore, the operation section 520 fixedto an operation bed enables to operate the first second operation unit530A and the second operation unit 530B.

As illustrated in FIG. 73 in enlarged view, the operation units 530A and530B are disposed diagonally so that portions closer to the connectionsheath 515 are placed closer to each other. Two operation sections 506Aand 506B (or two operation sticks 531A and 531B) are disposed at anglesbetween 20° to 100°. Disposing the operation sections 506A and 506B withthe opening angle relative to an operator facilitates the operator'soperation, thus improving operability. In addition, the width of theoperation section 520 closer to the connection sheath 515 can bereduced. Also, as illustrated in FIG. 43, dispositions, i.e., horizontaldirection, of the arm sections 302A and 302B in an image obtainedthrough an object lens 23 of an observation device attached to theendoscope can coincide with dispositions, i.e., horizontal direction, ofthe operation units 530A and 530B. This improves correlation ofoperator's perception and actual inner-body movement, therebyfacilitating manipulation. Furthermore, less force is required for anoperator to operate only the operation sticks 531A and 531B and theoperation sections 506A and 506B of the procedure instruments 504A and504B. Dispositions having reverse correlation with respect to horizontalor vertical direction provide similar operational perception obtained bylaparoscopic instruments.

The configuration of the first operation unit 530A is explained.

As illustrated in FIGS. 73 to 75, the first operation unit 530A has abracket 551A fixed to the base 521. The bracket 551A is fixed so that anopening 552A is substantially orthogonal to the center line of the firstoperation unit 530A. A first rotation mechanism 561A is attached tohorizontal side surfaces of the bracket 551A. The first rotationmechanism 561A has a pair of support chips 562A and 563A that are fixedto place the opening 552A of the bracket 551A therebetween. A rotationshaft 564A is disposed to the support chip 562A. A rotation shaft 565Ais disposed to the support chip 563A. The rotation shafts 564A and 565 aare disposed coaxially. A frame 567A is supported by this pair ofrotation shafts 564A and 565 a so as to be freely capable of rotatingwith respect to the bracket 551. An opening of a rectangular frame 567Ais disposed orthogonal to the center line of the first operation unit530A. The operation stick 531A is inserted through the frame 567A. Theoperation stick 531A engaging with the frame 567A in rotating angles ofthe rotation shafts 564A and 565 a is inserted so as to be independentlycapable of tilting in the axial lines of the rotation shafts 564A and565A.

As illustrated in FIG. 76, the tip section 571A of the operation stick531A extends beyond the frame 567A. Ball rollers 572A are provided tothe tip section 571A. The ball rollers 572A are disposed to place thecenter line of the operation stick 531A therebetween. The line passingthrough the centers of two ball rollers 572A is parallel with the axiallines of the rotation shafts 564A and 565A of the first rotationmechanism 561A as illustrated, i.e., where the operation stick 531A isnot tilted. Distances Laa between the rotation shaft 564A and 565A andthe ball rollers 572A are, for example, 50 to 200 mm

Frames 580A of the second rotation mechanism 581A are further disposedso as to place the ball rollers 572A therebetween and slide on the ballrollers 572A. The frames 580A are supported rotatively by the pair ofrotation shafts 584A and 585A. The pair of the rotation shafts 584A and585A are disposed coaxially so that the axial lines are orthogonal to apair of rotation shafts 564A and 565A and also orthogonal to the centerline of the first operation unit 530A. The rotation shafts 584A and 585Aare supported by support chips 582 a and 583A each fixed on a verticalside surface of the bracket 551A.

The configuration of the rotation shafts 584A and 585A of the secondrotation mechanism 581A will be explained here. Since the rotationshafts 584A and 585A have the same configuration, the rotation shaft584A will be explained for reference.

As illustrated in FIGS. 77 and 78, the rotation shaft 584A has a bearing591 fixed to the support chip 582A. The bearing 591 has a flange at anend of the cylinder so that the bearing 591 is fixed to the support chip582A by bolts passing through holes formed on the flange. Outer rings ofthe bearings 592 and 593 are press-fitted into the inside of thecylinder of the bearing 591 so as to be separate in the axial line. Adrive shaft 594 is supported by the bearings 592 and 593 rotativelyrelative to the bearing 591. The reduced diameter portion of the driveshaft 594 passes through the bearing 591.

An end section of the drive shaft 594 is enlarged in diametersubstantially to that of the bearing 591. A coil spring 596 is woundaround between an outer periphery of the drive shaft 594 and an outerperiphery of a cylindrical section of the bearing 591. Terminals 596Cand 596D are bent on both sides of the coil spring 596. A terminal 596Cis engaged with a groove formed on the flange 594C formed at an end ofthe drive shaft 594. An elemental wire of the coil spring 596 isrectangular in cross section. The rectangular shape may be a square or arectangle.

The drive shaft 594 is formed by a protrusion 594D and a flange 594C. Aplurality of screw holes are formed around the protrusion 594D. Eachrotative pin 597 is screwed into each screw hole disposed by 180 degreesoffset in a circumferential direction. An inner ring of the bearing 598is press-fitted and fixed into the protrusion 594D. A bearing 599 isattached to an outer periphery of the bearing 598. The bearing 599 has acylindrical section 599D having a flange. Inserted in advance into thecylindrical section 599D is a ring retainer 600 that depresses the ringretainer 600 toward a drive shaft 594 with a preload screw 602 via adiaphragm spring 601. A plurality of through-holes 599C are formed onthe flange of the bearing 599 at equal intervals in a circumferentialdirection. The through-holes 599C are disposed corresponding to thedisposition of the screw holes of the drive shaft 594. The diameter ofthe through-hole 599C is greater than that of a head portion of therotative pin 597. That is, the through-hole 599C has freeplay.

Provided further to cover the flange 594C of the bearing 594 and thecoil spring 576 is a cylindrical cover 603. A notch 603C is formed on abase portion of the cover 603. The other terminal 596D of the coilspring 596 is hooked at the notch 603C. In addition, a cylindricalsection 599D of the bearing 599 protruding from the cover 603 is fixedto the frames 580A by a pin.

Since an initial state of the coil spring 596 tightens the outerperipheries of the drive shaft 594 and the bearing 591, the drive shaft594 is joined to the bearing 591 by the coil spring 596. Since thebearing 591 is fixed to the support chip 582A, the drive shaft 594cannot rotate in the direction for tightening the coil spring 596. Butit is rotatable in a direction for loosening the coil spring 596. Incontrast, tilting movement provided by an operator of the operationstick 531A into the direction for tightening the coil spring 596 tiltsthe frames 580A that makes contact with the operation stick 531A.Tilting the frames 580A rotates the bearing 594 of the rotation shaft584A and the cover 603. Rotating the cover 603 loosens the coil spring596, thereby releasing the drive shaft 594 locked to the bearing 591.This results in allowing the drive shaft 594 to rotate, therebytransferring the rotation to the sprocket 595. The present symmetricdisposition of the rotation shaft 585A with respect to the operationstick 531A transfers the rotational movement of the operation stick 531Abut not the rotational movement for tightening the coil spring 596 fromthe sprocket 595. The operator's operation is transferred but a reactionforce by the sprocket 595 is maintained when the operator stops theoperation. Thus, the position is maintained, and the operation can befacilitated.

The coil spring 596 for use in such a spring clutch must be made from ahigh-hardness material. Use of a high-gravity material, e.g., iron, maycause an increase in the weight of the operation section 520. Therefore,a high-hardness and low-gravity material, e.g., duralumin (#2000) orextra super duralumin (#7000), may be used.

Meanwhile, loosening the coil spring 596 to release the locked state andtransferring the rotation via the coil spring 596 inevitably provide anexcessive force acting on the coil spring 596. In order to avoid such astate, a play is provided so that the head portion of the rotative pin597 of the drive shaft 594 makes contact to a periphery wall of thethrough-hole 599C of the bearing 594 after releasing the locked state.Rupture of the coil spring 596 is prevented by transferring the rotationby means of the rotative pin 597. The spring clutch having such aconfiguration is not limited to the present embodiment and can be usedfor a rotative structure for the procedure instrument or for theovertube.

In addition, the drive shaft 584 protruding from the flange of thebearing 591 is supported by bearings 613 and 614 so as to be rotativewith respect to the hollow shaft 612. A sprocket 595 is fixed to ahollow shaft 611. It should be noted that a rotative member for pushingand drawing a wire, e.g., a wire pulley, may be used in place of thesprocket 595.

The hollow shaft 612 is rotatively supported by the bearing 592 withrespect to the bearing 591. The drive shaft 594 and the hollow shaft 612both protruding over the sprocket 595 are inserted in a torque limiter611. The torque limiter 611 includes an outer 611C fixed to the hollowshaft 612 and an inner 611D fixed to the drive shaft 594. The inner 611Dand the outer 611C unitarily rotate until a predetermined torque isapplied. When excessive torque is applied, the outer 611C slides on theinner 611D; and thus, the rotation is not transferred.

As illustrated in FIG. 79 showing a configuration of the rotation shaft585A, the sprocket 595 is rotatively housed in a circular recessingsection 621 formed in the support chip 583A. A chain 622 is wound onteeth of the sprocket 595. A groove 623 is formed to the support chip583A. An end part of the chain 622 can be drawn into the groove 623 thatcontinues to the recessing section 621. The groove 623 is formed deeperthan the recessing section 621. Providing a gap 624 between the groove623 and the recessing section 621 prevents the chain 622 from beingentangled between the sprocket 595 and the recessing section 621, thusguiding the chain 622 into the groove 623.

A first bending wire 315A is fixed to an end part of the chain 622. Thefirst bending wire 315A bends the first bending parts 306 of the firstarm members 302A illustrated in FIG. 72 in a right-hand direction.

As illustrated in FIG. 79, the first bending wire 315A is drawn into anadjuster 641 disposed at an end part of the groove 623 of the supportchip 583A and introduced into a connection sheath 515 together with thecoil sheath passing through the coil sheath 642 connected to theadjuster 641. The first bending wire 315A is finally reached to thefirst arm member 302A. As illustrated in FIGS. 79 and 80, the adjuster641 has a coil base 651 fixed to the support chip 583A. A screw hole651A is formed to the coil base 651. An adjustment shaft 652 having athread on its outer periphery is screwed into the screw hole 651A. Theadjustment shaft 652 is a cylinder having a bottom. An end section 652Acorresponds to the bottom part into which a coil stopper 653 isinserted. The removal of the coil stopper 653 is prevented by engaging aflange-shaped protrusion 653D with an inner surface of the end section652A. The removal prevention in the reverse direction is provided byattaching a lock-screw 654 to the outer periphery. An end part of thecoil sheath is fixed to the coil stopper 653. The first bending wire315A passes through the adjustment shaft 652, followed by the coilstopper 653 and the coil sheath 642. The first bending wire 315Asometimes loosely extends during the step using the medical treatmentendoscope 501. In this case, inserting a fixture into the hole 652B ofthe adjustment shaft 652 and rotating them cause the coil sheath 642together with the adjustment shaft 652 to move in the axial direction.Forwarding the coil sheath 642 draws the first bending wire 315A fromthe coil sheath 642, thereby adjusting the loose state. Since the loosestate can be adjusted by means of a screw, it is not necessary todissemble the apparatus. Since the adjustment shaft 652 is rotativelyengaged with the coil stopper 653, rotating the adjustment shaft 652will never rotate the coil sheath 642.

Also, a sprocket 595 of the rotation shaft 584A is housed in the supportchip 582A, and the chain 622 is wound around the sprocket 595. The firstbending wire 315B (see FIG. 54) is attached to the chain 622. The firstbending wire 315B bends the first bending parts 306 of the first armmembers 302A illustrated in FIG. 72 in a right-hand direction. Anadjuster 641, also provided to the support chip 582A, can adjust theloose state by forwarding or drawing the coil sheath 642 having thefirst bending wire 315B therethrough. The first bending wire 315Binserted through the coil sheath 642 is introduced into the connectionsheath 515 together with the coil sheath 642 and reached to the firstarm member 302A.

As explained previously, the torque limiters 611 provided to therotation shafts 584A and 585A prevent the rotation of the rotation shaft585A from being transferred to the sprocket 595 when an excessive inputis provided from the operation stick 531A. This results in preventing anexcessive force from being applied to the first bending wire 315A.Considering a case assumed to use no torque limiter 611 may lead thepossibility where an excessive force is applied to the first bendingwire 315A. The torque limiter 611 for controlling the maximum torque canprevent the first bending wire 315A from being fractured. In addition,disposing the torque limiter 611, the sprocket 595, and the rotationshafts 564A and 565A in this order from the outside shorten the distancebetween the support chips 582 a and 583A, thereby downsizing the bracket551A. This increases freedom in layout and contributes to a downsizedand light-weight configuration.

The first rotation mechanism 561A will be explained next principallywith reference to FIG. 76.

A rotation shaft 564A has a similar configuration to the rotation shaft584A of the second rotation mechanism 581A except for the drive shaft594 attachably engaged with the frame 567A via the rotative pin 597 inthe rotative direction. Similarly, the other rotation shaft 565A has asimilar configuration to the rotation shaft 585A of the second rotationmechanism 581A except for the drive shaft 594 attachably engaged withthe frame 567A via the rotative pin 597 in the rotative direction.

Furthermore, a first bending wire 315D is joined to the sprocket 595 ofone of the rotation shafts 564A via the chain 622. A first bending wire315C is joined to the sprocket 595 of the other rotation shaft 565A viathe chain 622. The first bending wire 315C and the bending wire 315Dbend two first bending parts 306 of the first arm members 302Aillustrated in FIG. 72 in vertical opening directions. The adjuster 641,also provided to the support chip 562A and 563A, can adjust the loosestate by forwarding or drawing the coil sheath 642 having the firstbending wires 315C and 315D therethrough.

Next, the operation stick 531A will be described.

In the operation stick 531A as illustrated in FIGS. 76, 77, and 81,three cylindrical shafts 701, 702, and 703 bundled together are fixed toa tip portion to which a ball roller 572A is attached. The central shaft701 is longer than two shafts, i.e., shafts 702 and 703. The other twoshafts 702 and 703 barely reach to an abutment section 710 that servesas a rotative fulcrum making contact with the frame 567A of the firstrotation mechanism 561A. In contrast, the central shaft 701 extendsbeyond the abutment section 710.

A second bending slider 711 capable of freely forwarding or retractingin the axial direction is attached to the central shaft 701.Furthermore, a ratchet base 712 is fixed to a base end of the shaft 701.In the initial state, the second bending slider 711 cannot be forward orretracted because the second bending slider 711 is joined to the ratchetbase 712 by a connection plate 713 connected to the second bendingslider 711.

As illustrated in FIG. 82, a through-hole 712A is formed to the centerof the ratchet base 712. The through-hole 712A serves as an entrancefrom which the operation section 506A of the procedure instrument 504Ais inserted. Furthermore, a part 712B of an outer periphery of theratchet base 712 extends in a direction orthogonal to the axial linedirection. Putting a thumb here allows the second bending slider 711 tobe smoothly forwarded or retracted. A piston 715 slidable in a radialdirection is housed in the ratchet base 712. The piston 715 is urged bya coil spring 716 in a radial direction orthogonal to the axial linedirection. The protrusion 715A at the tip protrudes into a through-hole712A that is an insertion path for the procedure instrument 504A. A slit717 is formed on the piston 715. An engagement chip 717A is formed inthe slit 717. A first groove 718 of the connection plate 713 is engagedwith the engagement chip 717A. The first groove 718 is inserted throughthe slit 712C penetrating the ratchet base 712. Meanwhile, a verticalgroove 717C that is parallel in a radial direction may be formed on thepiston 715 as illustrated in FIG. 83. Inserting the tip portion of aclamping-bolt 716A (see FIG. 81) into the vertical groove 717C of anouter periphery of the ratchet base 712 can prevent the rotation of thepiston 715. This prevents the piston 715 from galling the connectionplate 713, thereby providing smooth movements of the piston 715 and theconnection plate 713 as explained later.

The tip of the connection plate 713 is joined to the second bendingslider 711 by a fulcrum pin 721 and extends substantially parallel inthe axial line from here toward the ratchet base 712. The recessingshape of the first groove 718 allows the engagement chip 717A of thepiston 715 to enter there, and a midpoint of the wall surface of the tipportion of the first groove 718 forms an inclination surface 718A. Theinclination surface 718A gradually widens the first groove 718 from themidpoint to the tip portion. A second groove 719 is formed at a furthertip portion than the first groove 718 is formed. The recessing shape ofthe second groove 719 allows the engagement chip 717A of the piston 715to enter there. The second groove 719 is deeper than the first groove718. The base end wall surface of the second groove 719 forms aninclination surface 719A. The inclination surface 719A gradually widensthe second groove 719 toward the tip portion. The first groove 718 ispositioned so that the second bending part 308 of the first arm member302A as illustrated in FIG. 72 becomes straightened. The second groove719 is positioned so that the second bending parts 308 bend to open thefirst arm member 302A. This allows the arm section 302A to close byengaging the first groove 718 with the piston 715, and allows the secondarm member 303A to open by engaging the second groove 719 with thepiston 715. As previously described, the engagement of the piston 715with the grooves 718 and 719 can be released with a small force sincethe inclination surfaces 718A and 719A are formed to the grooves 718 and719. This facilitates smooth switching of the engagement position of thepiston 715 with the grooves 718 and 719. As illustrated in FIG. 94, thespring 791 forces the second bending slider 711 and the connection plate713 to be positioned toward the tip portion by the spring force when theprocedure instrument 504A is not inserted and thus, the first groove 718engages with the piston 715. As illustrated in FIG. 96, the piston 715is pushed by the operation section 506A of the procedure instrument 504Awhen the procedure instrument 504A is inserted. Since this state of theengagement chip 717A can move up the inclination surface 718A, thesecond bending slider 711 can be drawn, and the second bending part 308can be opened. In this configuration, the procedure instrument 504A mustbe inserted to draw the second bending slider 711 because the tip of theprocedure instrument 504A can hardly be passed through the opening stateof the second bending part 308. As illustrated in FIG. 98, theengagement chip 717A makes contact with the inclination surface 719A aslong as the second bending slider 711 is drawn toward the base end. Thetension applied by the second bending wires 316A and 316B urges theslider 711 toward the tip. As illustrated in FIGS. 99 and 100, raisingthe piston 715 necessitates a significant force if the disposition angleof the inclination surface 719 is significantly 90°. If the dispositionangle is substantially horizontal, the piston 715 is spontaneouslyraised by the tension applied by the second bending wires 316A and 316Band therefore, the second bending slider 711 moves toward the tip, andthe second bending part 308 is closes. The suitable angle a of theinclination surface 719 is 60°≦α90°.

The second bending slider 711 is disposed coaxially with the axial lineof the operation stick 531A. Therefore, the compact first operation unit530A can be obtained. Formed at the base end thereof is an edge section711A for putting a thumb. A linear stroke 722 is built in a portionmaking contact with the shaft 701 to provide smooth sliding movement onthe shaft 701.

As illustrated in FIG. 84, two pipes 731 are attached to the tip of thesecond bending slider 711 so as to place the axial line between thepipes 731. Second bending wires 316A and 316B are passed respectivelythrough these pipes 731. The second bending wires 316A and 316B arefixed in the second bending slider 711 so that the second bending wires316A and 316B cannot be removed from the second bending slider 711.Disposing the second bending wires 316A and 316B symmetrically withrespect to the second bending slider 711 equalizes the force applied tothe second bending slider 711 and thus providing smooth movementthereof.

Two shafts 702 and 703, disposed further toward the tip, each have thepipe 731 inserted therethrough. The pipe 731 and the second bendingwires 316A and 316B are inserted through the shafts 702 and 703 disposedside by side. The shafts 702 and 703 each have a retainer member 741 atthe base end. Another pipe 742 is inserted from the tip through theretainer member 741. The tip of the pipe 742 is supported by acoil-receiving casing 743. The coil-receiving casing 743 is screwed inthe hole of the cylindrical pusher 744 and fixed there. An end portionof the coil spring 745 makes contact with the base end of the pusher744. The other end portion of the coil spring 745 is butted against theretainer member 741. The pusher 744 is urged by the coil spring 745toward the tip. In response to excessive force that draws the secondbending wires 316A and 316B, a force that relatively moves the coilsheath 747 to an operator's hand is applied and thus, the coil spring745 is compressed via the pusher 744. The coil spring 745 that is presetto a length exerting a predetermined force begins to contract if thepreset force is overreached. Since the second bending wires 316A and316B can further be drawn in accordance with the contraction of the coilspring 745, an excessive force is not applied to the second bendingwires 316A and 316B. A force applied to the second bending wires 316Aand 316B will never increase rapidly as long as the coil spring 745 canbe contracted if an excessive force is applied and therefore, the secondbending wires 316A and 316B will never be cut since overload mass iscurbed. Meanwhile, the coil spring 745 is compressed by a pusherretainer 746 screwed from the tips of the shafts 702 and 703. Since theinitial position of the pusher 744 can be adjusted in accordance withthe compression mass of the pusher retainer 746, differences in rigidityand bending force based on the coil springs 745 can be adjusted.

Furthermore, only the second bending wires 316A and 316B are extractedfrom the pipe 74. The second bending wires 316A and 316B are insertedthrough the pusher retainer 746 in the coil-receiving casing 743 andintroduced through the connection sheath 515 together with the coilsheath 747 to reach to the second bending part 308. The base end of thecoil sheath 747 is brazed to a tubular coil receiver 748 and fixed therein the coil-receiving casing 743. A coil-receiver-retainer 749 isscrewed from the tip through the coil-receiving casing 743. Thecoil-receiver-retainer 749 rotatively locking the coil receiver 748prevents the coil sheath 747 from being removed from the coil-receivingcasing 748, thereby preventing the pusher retainer 746 from beingtwisted. The lengths of the second bending wires 316A and 316Bcorresponding to the coil sheath 747 may sometimes have assembly error,and such error may sometimes be caused by the stretching of the secondbending wires 316A and 316B. Adjusting the screwing amount of thecoil-receiving casing 743 relative to the pusher 744 can adjust theerror.

As illustrated in FIGS. 84 and 85, a channel 801 for passing a procedureinstrument 504A therethrough is built in the central shaft 701. Thechannel 801 has, in order from the base end, a retainer 802 thataccommodates the procedure instrument 504A, a coil spring 803 insertedbetween the retainer 802 and the tip section 571A, and an extendablepipe 804 disposed in the coil spring 803. A hole 802A is formed in thecenter of the retainer 802. The hole 802A serves as an entrance forinserting the procedure instrument 504A therefrom. The hole 802A is atapered hole where the opening diameter increases toward the base end.The hole 802A having a funnel shape facilitates the insertion of adistal end of the insertion section 507A of the procedure instrument504A. The extendable pipe 804 has three pipes 805, 806, and 807 each ofwhich are different in diameter. These pipes are disposed coaxially. Aremoval stop 808 is attached to the pipes 805 and 806. A stopper 809locked to the removal stop 808 is attached to each pipe 806 and 807.That is, the extendable pipe 804 becomes the shortest when three pipes805, 806, and 807 substantially overlap. Extending each pipe 805, 806,and 807 until locking the stopper 809 to the removal stop 808 allows theextendable pipe 804 to be the longest. While the drawings illustrate thecompressed state of the coil spring 803, it restores under the no-loadcondition. The retainer 802 moves to the vicinity of a shaft 701 and tothe vicinity of the distal end of the piston 715. Since the retainer 802is disposed at the base end of the shaft 701 unless the procedureinstrument 504A is not inserted, the insertion section 507A of theprocedure instrument 504A can be inserted easily. The retainer 802 ispushed by the tip portion of the operation section 506A of the procedureinstrument 504A to be forwarded to the position illustrated in FIG. 84when the procedure instrument 504A is inserted. It should be noted thatthe extendable pipe 807 is not limited to a triple-pipe structure.

A space for passing the procedure instrument 504A therethrough isprovided in a tip section 571A that joins three shafts 701, 702, and703. An airtight valve 811 is provided on a path into which theprocedure instrument 504A is inserted and thus, the airtight conditioninside of the body subjected to a medical operation can be maintainedeven if the procedure instrument 504A is removed during the medicaloperation. The airtight valve 811 is made of, for example, a rubbersheet disposed to seal a hole 571B that communicates with the shaft 701.Formed to the rubber sheet is a notch into which an insertion portion ofthe procedure instrument 504A can be inserted. Passing the procedureinstrument 504A therethrough necessitates opening the notch. Removingthe procedure instrument 504A closes the notch, thereby maintaining theairtight condition. A retainer 812 is used to fix the airtight valve811. Fixing the retainer 812 onto the tip section 571A by screwsfacilitates exchanging the airtight valve 811 made of a rubber sheet.Meanwhile, the procedure instrument 504A is introduced into the bodythrough a hole 812A formed in the retainer 812. Forming the hole 812A soas to be tapered toward the tip facilitates the insertion of theprocedure instrument 504A.

The configuration of the second operation unit 530B is explained.

The second operation unit 530B has a symmetric configuration to thefirst operation unit 530A with respect to the horizontal center line ofthe operation section 520. A symbol “B” is added to some componentsincluded in the operation unit 530B to distinguish them from those ofthe first operation unit 530A.

A procedure instrument 504A inserted through the operation section 520will be explained next. Although only the procedure instrument 504A willbe explained here, it should be noted that the procedure instrument 504Bhas the same configuration. An end of each procedure instrument 504A and504B may be a high-frequency knife, a puncture needle, a snare, a clip,or other forceps.

As illustrated in FIG. 86, a treatment section 505A (see FIG. 72) and anoperation section 506A both provided to the tip of the procedureinstrument 504A are joined by an elongated flexible insertion section507A. The operation section 506A has a main body section 911 having acam 910 at the tip thereof. A slider 912 that drives the treatmentsection 505A is attached at the base end of the main body section 911rotatively in the axial line direction. In addition, a finger-hook ring913 is attached to the base end of the main body section 911.

As illustrated in FIG. 87, a ring 913 is joined to the main body section911 via an E ring 915. Operability is desirable since the ring 913 canbe rotated by the E ring 915 around the axial line. It should be notedthat a rubber-made protection member 916 may be used to be fitted to theinside of the ring 913 as illustrated in FIGS. 88 and 89. A groove 916Adetachable from the ring 913 is formed on an outer periphery of theprotection member 916. The use of rubber eases pain on fingers duringoperation. In addition, a detachable configuration is superior inmaintaining cleanliness and sterilization. Making the protection member916 of, for example, a silicone rubber, imparts chemical resistance andsterilization.

As illustrated in FIGS. 76 and 86, the tip portion of the cam 910 is ataper where an opening diameter decreases. When the taper surface 910Ais inserted through the operation stick 531A, the taper surface 910Aserves for pushing up the piston 715 and pressing the channel 801. Theouter diameter of the cam 910 is substantially the same as the innerdiameter of the shaft 701 so that the cam 910 is slidable on the shaft701. Four blade sections 921 extending in the axial line direction areprovided to the base end of the cam 910. As illustrated in FIG. 90A,each blade section 921 is provided only on the outer periphery of thecam 910. A side surface 921A in the circumferential direction forms atilted and curved surface from the center toward radially outward.

In addition, as illustrated in FIGS. 90 b and 91, a slope 921C directedto the tip together with a gap surface 921B standing in a radialdirection may be formed on the outer periphery of the tilted sidesurface 921A of the cam 910. A gap 921D between the tilted side surface921A and the outer periphery of the cam 910 is smoothly resolved by theslope 921C. A side surface 921E disposed opposite to the side surface921A in the blade section 921 has a space greater than the diameter ofthe piston 715 between the side surface 921A of another blade section921 adjacent in the circumferential direction and the side surface 921E.The side surface 921E is tilted in the direction the same as the tiltingdirection of the side surface 921A. The tilting direction of the sidesurface 921E is significant, i.e., forms a steep surface.

A main body section 911 is screwed into an inner hole of the cam 910 andfixed there. The outer diameter of the main body section 911 including apart inserted into the cam 910 and a stopper 922 having an increaseddiameter may be reduced gradually toward the base end. That is, FIG. 86shows an example in which a diameter d2 at the base end is smaller thana diameter d1 at the tip. An operation section 506A of the hole 571B hasa play relative to the operation stick 531A to prevent the main bodysection 911 from pushing up the piston 715 even if the operation section506A is tilted or bent. Also, the tip of the piston 715 protruding intothe shaft 701 is configured to have a correlation with the second groove719 so that a space is formed between the piston 715 and the secondgroove 719. Thus, the piston 715 is prevented from interfering with themain body section 911 and therefore, the forward movement or retractingmovement of the procedure instrument 504A can be smooth. In addition,the stopper 922 makes contact with a ratchet base 712 when the procedureinstrument 504A is inserted through the operation stick 531A andregulates so that the procedure instrument 504A is prevented from beingfurther pushed.

As illustrated in FIG. 92, a pipe 931 is fixed to a slider 912. Anoperation wire 932 for driving the treatment section 505A is passedthrough the pipe 931. The base end of the operation wire 932 and thebase end of the pipe 931 are locked to the slider 912 by an engagementmember 933. The pipe 931 passing through a slit 911A of the main bodysection 911 is extendably supported by a resin-made pipe retainer 934.An operation wire 932 passing through another pipe 935 fixed to the piperetainer 934 is extracted and enters an intermediate coupling 941together with the pipe 935, and is inserted into a metal-madesingle-layered coil 942 therein. Isolation is imparted to the pipe 935by coating it with a thermally-contracting tube.

As illustrated in FIG. 93, a coil receiver 943, to which the base end ofthe single-layered coil 942 is fixed, is housed in the base end of theintermediate coupling 941. The tip of the previously described pipe 935is inserted into the coil receiver 943. A diameter-contracting section941A is provided to the intermediate coupling 941 to prevent the coilreceiver 943 from being removed toward the tip. The single-layered coil942 is inserted into the multi-layered coil 951 at farther toward thetip than the diameter-contracting section 941A. The multi-layered coil951 is configured to have more than three coils disposed coaxially. Forexample, an innermost layer coil and an outermost layer coil are woundin the same direction, and an intermediate-layer coil is wound in theopposite direction in the case of three layer structure. This results inthat rotating of the innermost layer coil and the outermost layer coilin the coil-loosening direction tightens the intermediate-layer coil,thereby causing the intermediate layer coil to interfere with theinnermost layer coil. Thus, the rotation torque is transferred to thetreatment section 505A at the tip. Rotating in the opposite directioncauses the loosening intermediate layer coil to interfere with theoutermost layer coil, thereby transferring the rotation torque to thetreatment section 505A. In addition, using a metal-made multi-layeredcoil 951 improves the transferred rotation torque. A resin-made coil maybe used for obtaining insulation.

A coil receiver 952 is brazed to the multi-layered coil 951. The coilreceiver 952 is slidably inserted through a longitudinal groove 941Bformed on the insulative intermediate coupling 941. Accordingly themulti-layered coil 951 can engage with the intermediate coupling 941 inthe rotative direction, but not in the forward direction or theretracting direction. Meanwhile, a resin-made removal stop 953 isattached to the tip of the intermediate coupling 941. Since the removalstop 953 regulates the protrusion of the coil receiver 952, themulti-layered coil 951 will never be removed from the intermediatecoupling 941. Also, the coil receiver 952 will never make contact withthe main body section 911. This configuration will not affect the lengthof the multi-layered coil 951 even if the single-layered coil 942contracts or extends during a medical operation.

Also, the single-layered coil 942 can be brazed to the coil receiver 943that is slid toward the base end and extracted from the intermediatecoupling 941 after brazing the multi-layered coil 951 to the coilreceiver 952. Meanwhile, the intermediate coupling 941 should preferablybe made of high heat-resistance resin, e.g., PEEK (polyetheretherketone)taking the high temperature applied during the brazing operation intoaccount.

The outer periphery of the multi-layered coil 951 extracted from theintermediate coupling 941 is coated by an insulative tube 954. A fluororesin-made insulative tube 954 has lower sliding friction, thusproviding desirable rotation. The isolated and coated multi-layered coil951 passing through a winding-protection pipe 955 is extracted from ahole 910C formed at the tip of the cam 910.

The main body section 911 should preferably be made of a metal materialtaking durability into account. In this case, providing insulation tothe operation section 506A realizes a procedure instrument 504A for usein a medical operation with a high-frequency apparatus. Therefore, theuse of a resin in the removal stop 953, intermediate coupling 941,thermally-contracting tube of the pipe 935, pipe retainer 934, andslider 912 reliably isolates the main body section 911 from theoperation wire 932 and coils 942 and 951. This results in usinghigh-frequency waves with the procedure instrument 504A such as anincision knife or a high-frequency forceps. Apparatuses of this type canbe used compatibly. Insulation coating onto the multi-layered coil 951may not be necessary unless the procedure instrument is of a highfrequency application-type apparatus. In this case, increasing thethickness of the multi-layered coil 951 corresponding to the thicknessof the thermally contracting tube for use as a coating will provide amore rotative procedure instrument. The thickness of the thermallycontracting tube utilized for the single-layered coil 942 will provide amore significant resistance against compression or expansion.

Consequently, steps for carrying out operations using the medicaltreatment endoscope 501 will be explained. Meanwhile, a case will beexplained as follows where an endoscope is introduced from a mouth as anatural orifice of a patient, a procedure instrument is introduced froman opening formed in a stomach into an abdominal cavity to grasp tissue.It should be noted that operations can be carried out through anotherorgan or another path. Although we concentrate on the procedureinstrument 504A and the first operation unit 530A in the explanation,the procedure instrument 504B and the operation unit 530B can be usedindependently because they are mere symmetric components.

Two procedure instruments 504A and 503B are inserted into the medicaltreatment endoscope 501. The procedure instrument 504A is inserted intothe first operation unit 530A. As schematically illustrated in FIG. 94,when the procedure instrument 504A is not inserted yet, the piston 715provided to the ratchet base 712 at the tip of the first operation stick531A engages with the first groove 718 of the connection plate 713 andlocks the connection plate 713. Locking the connection plate 713prevents the second bending slider 711 from moving since the ratchetbase 712 is unmovable. This corresponds to a position where the secondbending part 308 becomes straightened. That is, the second bending part308 is always straightened in the medical treatment endoscope 501 whenthe procedure instrument 504A is inserted. As illustrated in FIG. 95,forwarding the operation section 506A into the first operation stick531A pushes up the piston 715 with the taper surface 910A of the cam 910at the tip of the operation section 506A. As illustrated in FIG. 96, thepiston 715 being capable of moving up the inclination surface 718A ofthe first groove 718 of the connection plate 713 allows the secondbending slider 711 to be controlled in the direction indicated by anarrow shown in the drawing.

As illustrated in FIG. 76, the insertion section 507A of the procedureinstrument 504A passing through the channel 801 is introduced into achannel in the connection sheath 515. The insertion section 507A furtherpassing through the endoscope insertion section 503 is introduced to thetip of the first arm member 302A. Similarly, the procedure instrument504B inserted into the operation stick 531B of the operation unit 530Bis introduced to the tip of the second arm member 303A.

After closing the arm sections 302A and 303A having the procedureinstruments 504A and 504B previously passing therethrough, the endoscopeinsertion section 503 is introduced into a body cavity from an openingpreviously formed in a stomach wall. In addition, the endoscopeinsertion section 503 may be passed through an overtube previouslyinserted into a body.

A section to be treated is confirmed while observing with a monitor animage obtained by an endoscopic image-pickup device provided to the tipof the endoscope insertion section 503. At this time, a first operatormanipulates an angle knob 512 of the endoscope insertion section 502 andbends a third bending part 203B. Furthermore, a second operator bendsthe second bending part 308 and the first bending part 306 if necessary.

Bending the second bending part 308 necessitates retracting the secondbending slider 711 provided to the operation sticks 531A and 531B. Asillustrated in FIG. 96, retracting the second bending slider while thepiston 715 is elevated causes the engagement chip 717A of the piston 715to go up the inclination surface 718A, thereby causing the connectionplate 713 to slide on the piston 715 as illustrated in FIG. 97. Thesecond bending slider 711 cannot be farther retracted after the piston715 is housed in the second groove 719 as illustrated in FIG. 98. Thesecond bending part 308 as illustrated in FIG. 72 bends at thisposition, causing the first arm member 302A to open. In addition, sincethe second groove 719 is shallower than the first groove 718, a space Ssis formed between the cam 910 and the main body section 911 of theoperation section 506A when the piston 715 engages with the secondgroove 719. Absence of slide between the main body section 911 and thepiston 715 allows smooth extension and retraction of the main bodysection 911.

Furthermore, bending the first bending part 306 necessitates tilting theoperation sections 506A and 506B of the procedure instruments 504A and504B while observing the endoscopic image.

As illustrated in FIG. 75, tilting the operation section 506A upwardlyrelative to the operator causes the rotation shafts 564A and 565A of thefirst rotation mechanism 561A to rotate in accordance with the tiltingangle. The rotation of the sprocket 595 attached to the rotation shafts546A and 565 a causes extension and retraction of the first bendingwires 315A and 315B attached to the chain 622, thereby bending the firstbending part 306 upwardly. In contrast, tilting the operation section506A downwardly relative to the operator causes the rotation shafts 564Aand 565A of the first rotation mechanism 561A to rotate in the directionreverse to the upward tilting direction in accordance with the tiltingangle. The reverse rotation of the sprocket 595 attached to the rotationshafts 546A and 565 a causes extension and retraction of the firstbending wires 315A and 315B attached to the chain 622, thereby bendingthe first bending part 306 downwardly.

Tilting the operation section 506A in a right-hand direction relative tothe operator causes the rotation shafts 584A and 585A of the secondrotation mechanism 581A to rotate in accordance with the tilting angle.The rotation of the sprocket 595 attached to the rotation shafts 584Aand 585A causes extension and retraction of the first bending wires 315Cand 315D attached to the chain 622, thereby bending the first bendingpart 306 in the right-hand direction. In contrast, tilting the operationsection 506A in a left-hand direction relative to the operator causesthe rotation shafts 584A and 585A of the second rotation mechanism 581Ato rotate in the reverse direction in accordance with the tilting angle.The reverse rotation of the sprocket 595 attached to the rotation shafts584A and 585A causes extension and retraction of the first bending wires315C and 315D attached to the chain 622, thereby bending the firstbending part 306 in the left-hand direction.

Since the second rotation mechanism 581A is not driven when the firstrotation mechanism 561A is driven, and the first rotation mechanism 561Ais not driven when the second rotation mechanism 581A is driven, eachbending can be obtained without being affected by these rotationmechanisms. Meanwhile, tilting the operation section 506A drives thefirst and second rotation mechanisms 561A and 581A in accordance withthe tilting ratio with respect to the vertical and horizontaldirections, thereby bending the first bending part 306 diagonally in thedirection the same as the tilting direction of the operation section506A. Since the center or barycenter of the operation stick 531A in thelongitudinal direction is configured to substantially coincide with thepositions of the rotation shafts 546A, 565A, 584A, and 585A, theoperation stick 531A and the operation section 506A of the procedureinstrument 504A during hands-free operation by the operator will notdescend with gravity; therefore, erroneous operation can be prevented.

A necessary force is optimized to operate the first bending part 306 bymeans of a non-electric wire-assisted operation. To be more specific, aportion of the operation stick 531A operated by the operator who inputsa force is decelerated by separating and offsetting the portion from therotation shafts 546A, 565A, 584A, and 585A. As illustrated in FIG. 77,since a deceleration ratio is obtained corresponding to a ratio betweena distance Lr an a radius Rs of the sprocket 595, the bending operationcan be carried out with a small force while downsizing the operationsection 520. In this case the distance Lr indicates a length between thebase end section of the operation section 506A of the procedureinstrument 504A. In addition, the deceleration enhances resolution,thereby enabling accurate bending operation.

As illustrated in FIGS. 76 and 77, since the point of the secondrotation mechanism 581A to which a force is transmitted from the firstoperation stick 531A is offset toward the tip relative to the rotationshafts 564A and 565A such as a roller bearing 572A as illustrated inFIG. 77, the force necessary at the transfer position is decreased, andfriction among components can be reduced. This decreases the rigidityrequired for components used there and obtains a small and light-weightoperation section 520. Also, the use of the ball roller 572A at thepoint of the second rotation mechanism 581A to which the force istransferred from the first operation stick 531A reduces the friction dueto the second rotation mechanism 581A when rotating the first operationstick 531A vertically, thereby reducing the necessary force for thevertical operation.

Grasping tissue necessitates adjusting the position of a forceps memberthat is opened or closed by the operation section 506A of the procedureinstrument 504A. For example, pushing the operation section 506A intothe first operation stick 531A causes the treatment section 505A toprotrude further from the first arm member 302A. Also, retracting theoperation section 506A from the first operation stick 531A causes thetreatment section 505A to be retracted into the first arm member 302A.As illustrated in FIG. 99, since this state of the cam 910 is hooked onthe piston 715, the procedure instrument 504A will not be removed fromthe first operation stick 531 A undesirably.

Adjusting the direction of the procedure instrument 504A around theaxial line necessitates the main body section 911 of the operationsection 506A to rotate around the axial line. Thus, rotational torque isinput into the multi-layered coil 951 that is engaged to theintermediate coupling 941 in the rotational direction as illustrated inFIGS. 92 and 93. In the multi-layered coil 951, two coils adjacent toeach other in a radial direction interfere with each other while theyare tightened or loosened based on their combination of the windingdirection and the rotational direction of the operation section 506A andthus, rotational torque is transferred. Since the treatment section 505Ais fixed to the tip of the multi-layered coil 951, the transferredrotational torque rotates the treatment section 505A around the axialline. The rotation in the vicinity of the operator's hand is stoppedafter confirming that a desirable direction is obtained by means of anendoscopic image.

The slider 912 is forwarded after adjusting the direction and positionof the treatment section 505A. The operation wire 932 moves anopening-and-closing mechanism of the treatment section 505A to open apair of forceps members. The single-layered coil 942 receives anextension force generated by pushing the operation wire 932. Theextension force is not applied to the multi-layered coil 951 because themulti-layered coil 951 is not engaged with the operation section 506A inthe extension and retraction directions. This allows the treatmentsection 505A to be adjusted even if the forceps members are opened.Consequently, retracting the slider 912 causes the forceps members toclose and grasp tissue. The compression force generated temporarily isreceived by the single-layered coil 942.

The procedure instruments 504A and 504B are retracted from the medicaltreatment endoscope 501 after completing necessary treatments. Theprocedure instruments 504A and 505B are also retracted from the medicaltreatment endoscope 501 in order to exchange procedure instrumentsnecessary for a treatment. As illustrated in FIG. 99, the operationsection 506A is rotated around the axial line after the cam 910 abutsthe piston 715. The piston 715 is pushed up along the tilted sidesurface 921A of the blade section 921 of the cam 910. As illustrated inFIG. 100, providing the tilted side surface 921A enables to push up thepiston 715 with a small force. Meantime, as illustrated in FIGS. 90 and91, the procedure instrument 504A will never be rotated excessively ifthe gap surface 921B is provided. Furthermore, providing the slope 921Cfacilitates offsetting the piston 715 from the cam 910 in an axial linedirection (thrust direction), thereby removal is easy. Meantime, it ispreferable that the entire cam 910 should be made of a metal in view ofbreakage protection. In addition, the cam 910 may be made of POM(polyoxymethylene) that has desirable slidability in view offacilitating operation in an extension and retraction operations in thefirst operation stick 531A.

However, the treatment sections 505A and 505B cannot be removed if thesecond bending part 308 of the arm sections 302A and 303A is opened, andthe engagement of the piston 715 and the cam 910 can be released. Thepiston 715 pushed up by the cam 910 in the operation section 520 isconfigured to automatically restore the second bending part 308 to astraightened state. That is, pushing up the piston 715 and releasing theengagement with the second groove 719 retract the second bending slider711 with tension applied by the second bending wires 316A and 316B and aresilience of the coil spring 745. This results in causing the secondbending part 308 to restore into the straightened state. In addition, aresilient part like the spring 792 as illustrated in FIG. 84 may beadded to prevent energetic restoration of the second bending slider 711.Consequently, the medical treatment endoscope 501 is removed from thebody after removing the procedure instrument 504A.

Next, a modified example of the present embodiment will be described asfollows.

As illustrated in FIG. 101, the operation sections 1001A and 1001B eachfor operating the second bending slider 711 may be fixed to the brackets551A and 551B in parallel with each axial line of the operation sticks531A and 531B. The operation sections 1001A and 1001B each have anextendable and retractable slider. Moving the slider causes the wire inthe coil sheath 1002 to be extended or retracted. As illustrated in FIG.102, the coil sheath 1002 is fixed to the coil receiver 1003 attached tothe ratchet base 712. A pipe 1004 is passed through the coil receiver1003. The pipe 1003 passing through the coil sheath 1002 is rotativelyengaged with the second bending slider 711via the wire receiver 1005together with the second bending wires 316A, 316B. A wire 1006 joined tothe sliders of the operation sections 1001A and 1001B is passed throughthe pipe 1004. Retracting the sliders of the operation sections 1001Aand 1001B moves the wire 1006, thereby drawing the second bending slider711 and opening the second bending part 308. In this configuration, theoperation section 520 can be downsized and thus, operation of the secondbending part 308 can be facilitated. Also, this configuration preventsthe movement of the operation sticks 531A and 531B during the operationof the second bending part 308. Thus, grasped tissue will never be movedunexpectedly.

As illustrated in FIG. 103, the base end of the cam 910 may be theinclination surface 1010. Drawing the procedure instrument 504A from thefirst operation stick 531A causes the piston 715 to move up theinclination surface 1010, thereby removing the procedure instrument504A. The procedure instrument 504A cannot be removed with a force basedon the retraction of the procedure instrument 504A toward the operatorduring a treatment. Further additional force will provide retraction. Inthis configuration, the procedure instrument 504A can be removed withoutrotating the operation section 506A.

In addition, operations for significant rotations of the procedureinstruments 504A and 504B will be explained with reference to FIGS. 104and 105. This includes cases where we intend to adjust the treatmentsection 505A in the optimum direction to grasp tissue. As illustrated inFIG. 104, the slider 912 is held with an index finger and a middlefinger. The hand-held state of the slider 912 is rotated in a clockwisedirection by 90°. The index finger and the middle finger are withdrawnfrom the slider 912 after rotating the slider 912 and the main bodysection 911 to the positions illustrated in FIG. 105. The hand notholding the slider 912 is rotated in a counterclockwise direction by90°to the position illustrated in FIG. 104. This state of the insertionsection 507A of the procedure instrument 504A has friction relative tochannels in a first operation stick 531A and the second arm member 302A.To be more specific, the channels are a channel 801, a channel in theconnection sheath 515, and a channel in the endoscope insertion section503. Therefore, the insertion section 507A will not rotate in thecounterclockwise direction with a mere touch with the slider 912 andthus, its disposition is maintained. Repeating the above steps enables90° feed operation of the procedure instrument 504A.

As illustrated in FIG. 106, the medical treatment endoscope 501 may bepassed through the overtube 90. The first operator handling theendoscope insertion section 502 conducts ordinary endoscopic operationwith his/her left hand while operating the endoscope insertion section503 and overtube 90 with his/her right hand. The intention to bend theovertube 90 improves the approachability to the object position in theabdominal cavity.

Sixth Embodiment

A procedure instrument usable with an endoscope is illustrated in FIGS.107 and 108.

A procedure instrument 1100 has a overcoat tube 1101 constituting aflexible and elongated insertion section. An operation section 1102 isprovided on the base end of the overcoat tube 1101. A needle section1103 serving as a treatment section is passed through the overcoat tube1101 extendably and retractably. The tip portion of the needle section1103 protrudes from the opening of the tip of the overcoat tube 1101 asillustrated in FIG. 107.

The needle section 1103 has a second coil 1111 passed through theovercoat tube 1101. The connecting part 1112 joins the tip of the secondcoil 1111 to the base end of the first coil 1113. The first coil 1113 issubstantially the same as the second coil 1111 in outer diameter. Theinner diameter of the first coil 1113 is greater than that of the secondcoil 1111. A supporting section 1116 for supporting a pair of needles1114 is attached to the tip of the first coil 1113. As illustrated inFIGS. 109 and 110, a supporting section 1116 has two parallel throughholes each having a hollow needle 1114 passing therethrough extendablyand retractably. The pair of the needles 1114 are bending at the baseend supported by the supporting section 1116 to spread with respect toan axial line. The acute tips are disposed substantially parallel at apredetermined distance. A slit 1117 is formed at the acute tip along theaxial line. A pusher wire 1118 is passed through each needle 1114. Thepusher wire 1118 extracted from the base end of the needle 1114 isjoined to the operation wire 1121 in the first coil 1113 via theconnecting part 1020. The operation wire 1121 passing through the secondcoil 1111 extendably and retractably is introduced to the operationsection 1102. Meantime, the outer diameter of the connecting part 1020is greater than that of the operation wire 1121. However, since theinner diameter of the first coil 1111 is significant, extendable andretractable movement can be obtained in the first coil 1113.

The base end of the second coil 1111 is a hard section 1131 that isfixed to the operation section main unit 1132 of the operation section1102. The operation wire 1121 passing through the operation section mainunit 1132 is joined to the slider 1133 attached to the operation sectionmain unit 1132 extendably and retractably. A finger-hook ring 1134 isattached to an end of the operation section main unit 1132 rotativelyaround the axial line. Sliding back and forth the slider 1133 relativeto the operation section main unit 1132 while inserting a thumb into thefinger-hook ring 1134 and supporting the slider 1133 with an indexfinger and a middle finger provide extending or retracting movement tothe pusher wire 1118 relative to the overcoat tube 1101. As illustratedin FIG. 111, the pusher wire 1118 can be extended until protruding fromthe tip of the needle 1114. Meantime, a coating may be applied to thepusher wire 1118 for smooth extension and retraction of the pusher wire1118 in the needle 1114.

The base end of the overcoat tube 1101 is fixed to the overcoat tube endmember 1141. The overcoat tube end member 1141 can move along the hardsection 1131 of the second coil 1111. Tightening the fixing screw 1142allows the overcoat tube 1101 to be fixed to a front end section 1132Aof the operation section main unit 1132.

FIG. 112 illustrates a retainer 1201 loaded in the needle 114. Theretainer 1201 has two anchors 1202 each housed in the needle 1114, athread 1203 joining two anchors 1202, and a fastener plate 1204 havingthe thread 1203 passing therethrough.

Manipulation using the procedure instrument 1100 will be explained.

The retainer 1201 is loaded first in the procedure instrument 1100. Tobe more specific, each anchor 1202 is housed in the inside of the acuteend of each needle 1114, and the thread 1203 is extracted from the slit1117. A fixing screw 1142 is loosened after loading the retainer 1201.As illustrated in FIG. 113, a overcoat tube end member 1141 is extendedrelative to the operation section main unit 1132. As illustrated in FIG.114, the pair of the needles 114 are drawn into the overcoat tube 1101and housed there.

The overcoat tube 1101 is next inserted into a body cavity through achannel of the endoscope, and the overcoat tube 1101 is protruded fromthe tip of the endoscope. As illustrated in FIG. 115, an operationsection main unit 1132 is pushed into the overcoat tube end member 1141after loosening the fixing screw 1142. As illustrated in FIG. 115, theneedle 1114 protrudes from the overcoat tube 1101. The acute ends of theneedle 1114 opens by releasing the urging force applied by the overcoattube 1101. Tightening this state of fixing screw 1142 of the overcoattube end member 1141 causes the needle section 1103 of the overcoat tube1101 to be fixed.

As illustrated in FIG. 116, forwarding the procedure instrument 1100relative to the endoscope provides protrusion of the needle 1114 intothe inner wall Wb of a body cavity. The acute ends and the slits 1117penetrate the inner wall Wb of a body cavity and protrude into theexterior of the body cavity. The thread 1203 extracted from the slit1117 is reached to the endoscope through tissue. The fastener plate 1204exists in the endoscope.

As illustrated in FIG. 117, forwarding the slider 1133 causes the pusherwire 1118 to be forwarded. As illustrated in FIG. 118, the pusher wire1118 pushes the anchor 1202 from the opening at the tip of the needle1114. The procedure instrument 1100 is subsequently retracted relativeto the endoscope. As illustrated in FIG. 112, the pair of needles 1114are removed from the inner wall Wb of a body cavity. The anchor 1202previously discharged from the needles 1114 remains in the exterior ofthe body cavity. Accordingly, the thread 1203 penetrates the inner wallWb of a body cavity. Drawing the thread 1203 extracted in loop withforceps, which is not shown in the drawing, from the fastener plate 1204causes the anchor 1202 to be attracted to the fastener plate 1204. Sincethe anchor 1202 closely contacting the outer surface of the inner wallWb of a body cavity is unremovable, the fastener plate 1204 isrelatively compressed to the inner surface of the inner wall Wb of abody cavity, and the inner wall Wb of a body cavity is tightened by thethread 1203.

Since the needles 1114 and the pusher wire 1118 are provided to only thetip of the procedure instrument 1100, the operation wire 1121 can besignificant in size. The significant size of the operation wire 112improves power transmission and enhances the operability of the pusherwire 1118. Although the connection part of the pusher wire 1118 and theoperation wire 1121 may be significant in diameter, providing the firstcoil 1113 having a greater inner diameter enables extension andretraction of the pusher wire 1118 and power transmission. This resultsin enabling smooth releasing of the retainer 1201 in a case where theovercoat tube 1101 bends complexly.

Although the present invention has been described with respect to itspreferred embodiments, the present invention is not limited to theembodiments described above. The configuration of the present inventionallows for addition, omission, substitution and further replacementwithout departing from the spirit and scope of the present invention.The present invention is not limited to the above descriptions but islimited only by the appended claims.

1. A treatment instrument comprising: a sheath capable of a bendingoperation; an arm section protruding from the tip of the flexible sheathand being capable of the bending operation; an operation stick allowingan operator to carry out the bending operation of the arm section; afirst rotation mechanism which is joined to the operation stick andbends the arm section; a second rotation mechanism which is joined tothe operation stick and bends the arm section; and a second rotationmechanism which is joined to the operation stick and bends the armsection in a direction substantially orthogonal to the direction of thearm section bent by the first rotation mechanism.
 2. The treatmentinstrument according to claim 1, further comprising: an operationsection provided with the first rotation mechanism and the secondrotation mechanism; and an operation section which is distant from theoperation section for carrying out the bending operation of the sheath.3. The treatment instrument according to claim 1, wherein: the firstrotation mechanism and the second rotation mechanism each have arotative shaft rotating in accordance with a tilting direction and atilting amount of the operation stick; and the rotative shaft is offsetfrom a position at which a force is input when the operator carries outthe tilting operation for the operation stick.
 4. The treatmentinstrument according to claim 3, wherein the rotative shaft is disposedat a point which substantially corresponds to the barycenter or thelongitudinal center of the operation stick.
 5. The treatment instrumentaccording to claim 1, wherein: the second rotation mechanism has arotative shaft rotating in accordance with the tilting direction and thetilting amount of the operation stick; and a joint position of thesecond rotation mechanism and the operation stick is offset from therotative shaft.
 6. The treatment instrument according to claim 5,further comprising a roller bearing is disposed at a joint position ofthe second rotation mechanism and the operation stick.
 7. The treatmentinstrument according to claim 1, wherein: the first rotation mechanismand the second rotation mechanism each have a rotative shaft rotating inaccordance with the tilting direction and the tilting amount of theoperation stick; a rotative member is fixed to the rotative shaft; awire joined to the rotative member is configured to bend the armsection; and the joint position between the operation stick and thefirst rotation mechanism or the second rotation mechanism, the rotativemember, and a torque limiter for intermittently connecting the torquetransmitted from the operation stick to the rotative member are disposedin an axial line direction.
 8. The treatment instrument according toclaim 1, wherein: the first rotation mechanism and the second rotationmechanism each have a rotative shaft rotating in accordance with thetilting direction and the tilting amount of the operation stick; arotative member is fixed to the rotative shaft; a wire joined to therotative member is configured to bend the arm section; and a clutch isprovided to the rotative shaft, restricts the rotation corresponding toa rotation torque input from the rotative member, and tolerates therotation corresponding to a rotation torque input from the operationstick.
 9. The treatment instrument according to claim 8, wherein theclutch has a spring, and is provided with a pin which engages in therotational direction after the spring is deformed by a predeterminedamount and which transfers the rotation.
 10. The treatment instrumentaccording to claim 1, wherein the arm section comprises a pair of armsections, and each arm section has the operation stick, the firstrotation mechanism, and the second rotation mechanism; and the pair ofthe operation sticks are diagonally disposed at a predetermined angle soas to open relative to the operator.
 11. The treatment instrumentaccording to claim 1, further comprising a viewing unit for observing atip farther than the flexible sheath.
 12. The treatment instrumentaccording to claim 11, wherein the sheath is a flexible.